Engineerblogger
Jan 16, 2013
John Maeda, President of the Rhode Island School of Design, delivers a funny and charming talk that spans a lifetime of work in art, design and technology, concluding with a picture of creative leadership in the future. Watch for demos of Maeda’s earliest work -- and even a computer made of people.
John Maeda is the president of the Rhode Island School of Design, where he is dedicated to linking design and technology. Through the software tools, web pages and books he creates, he spreads his philosophy of elegant simplicity.
Source: TED
Additional Information:
Wednesday, 16 January 2013
Engineer making rechargeable batteries with layered nanomaterials
Engineerblogger
Jan 16, 2013
A Kansas State University researcher is developing more efficient ways to save costs, time and energy when creating nanomaterials and lithium-ion batteries.
Gurpreet Singh, assistant professor of mechanical and nuclear engineering, and his research team have published two recent articles on newer, cheaper and faster methods for creating nanomaterials that can be used for lithium-ion batteries. In the past year, Singh has published eight articles -- five of which involve lithium-ion battery research.
"We are exploring new methods for quick and cost-effective synthesis of two-dimensional materials for rechargeable battery applications," Singh said. "We are interested in this research because understanding lithium interaction with single-, double- and multiple-layer-thick materials will eventually allow us to design battery electrodes for practical applications. This includes batteries that show improved capacity, efficiency and longer life."
For the latest research, Singh's team created graphene films that are between two and 10 layers thick. Graphene is an atom-thick sheet of carbon. The researchers grew the graphene films on copper and nickel foils by quickly heating them in a furnace in the presence of controlled amounts of argon, hydrogen and methane gases. The team has been able to create these films in less than 30 minutes. Their work appears in the January issue of ACS-Applied Materials and Interfaces in an article titled "Synthesis of graphene films by rapid heating and quenching at ambient pressures and their electrochemical characterization."
The research is significant because the researchers created these graphene sheets by quickly heating and cooling the copper and nickel substrates at atmospheric pressures, meaning that scientists no longer need a vacuum to create few-layer-thick graphene films and can save energy, time and cost, Singh said.
The researchers used these graphene films to create the negative electrode of a lithium-ion cell and then studied the charge and discharge characteristics of this rechargeable battery. They found the graphene films grown on copper did not cycle the lithium ions and the battery capacity was negligible. But graphene grown on nickel showed improved performance because it was able to store and release lithium ions more efficiently.
"We believe that this behavior occurs because sheets of graphene on nickel are relatively thick near the grain boundaries and stacked in a well-defined manner -- called Bernal Stacking -- which provides multiple sites for easy uptake and release of lithium ions as the battery is discharged and charged," Singh said.
In a second research project, the researchers created tungsten disulfide nanosheets that were approximately 10 layers thick. Starting with bulk tungsten disulfide powder -- which is a type of dry lubricant used in the automotive industry -- the team was able to separate atomic layer thick sheets of tungsten disulfide in a strong acid solution. This simple method made it possible to produce sheets in large quantities. Much like graphene, tungsten disulfide also has a layered atomic structure, but the individual layers are three atoms thick.
The researchers found that these acid-treated tungsten disulfide sheets could also store and release lithium ions but in a different way. The lithium is stored through a conversion reaction in which tungsten disulfide dissociates to form tungsten and lithium sulfide as the cell is discharged. Unlike graphene, this reaction involves the transfer of at least two electrons per tungsten atom. This is important because researchers have long disregarded such compounds as battery anodes because of the difficulty associated with adding lithium to these materials, Singh said. It is only recently that the conversion reaction-based battery anodes have gained popularity.
"We also realize that tungsten disulfideis a heavy compound compared to state-of-the-art graphite used in current lithium-ion batteries," Singh said. "Therefore tungsten disulfide may not be an ideal electrode material for portable batteries."
The research appeared in a recent issue of the Journal of Physical Chemistry Letters in an article titled "Synthesis of surface-functionalized WS2 nanosheets and performance as Li-ion battery anodes."
Both projects are important because they can help scientists create nanomaterials in a cost-effective way. While many studies have focused on making graphene using low-pressure chemical processes, little research has been tried using rapid heating and cooling at atmospheric pressures, Singh said. Similarly, large quantities of single-layer and multiple-layer thick sheets of tungsten disulfide are needed for other applications.
"Interestingly, for most applications that involve this kind of battery research and corrosion prevention, films that are a few atoms thick are usually sufficient," Singh said. "Very high quality large area single-atom-thick films are not a necessity."
Other Kansas State University researchers involved in the projects include Romil Bhandavat and Lamuel David, both doctoral students in mechanical engineering, India, and Saksham Pahwa, a visiting undergraduate student, India. The graphene research involved University of Michigan researchers, including Zhaohui Zhong, assistant professor of electrical engineering and computer science, andGirish Kulkarni, doctoral candidate in electrical engineering.
Singh's work has been supported by the National Institute of Standards and Technology and the Kansas National Science Foundation Experimental Program to Stimulate Competitive Research program.
Singh plans future research to study how these layered nanomaterials can create better electrodes in the form of heterostructures, which are essentially three-dimensional stacked structures involving alternating layers of graphene and tungsten or molybdenum disulfide.
Source: Kansas State University
Additional Information:
Jan 16, 2013
 |
| We study the process of graphene growth on Cu and Ni substrates subjected to rapid heating (approximately 8 °C/s) and cooling cycles (approximately 10 °C/s) in a modified atmospheric pressure chemical vapor deposition furnace. Electron microscopy followed by Raman spectroscopy demonstrated successful synthesis of large-area few-layer graphene (FLG) films on both Cu and Ni substrates. The overall synthesis time was less than 30 min. Further, the as-synthesized films were directly utilized as anode material and their electrochemical behavior was studied in a lithium half-cell configuration. FLG on Cu (Cu-G) showed reduced lithium-intercalation capacity when compared with SLG, BLG and Bare-Cu suggesting its substrate protective nature (barrier to Li-ions). Although graphene films on Ni (Ni-G) showed better Li-cycling ability similar to that of other carbons suggesting that the presence of graphene edge planes (typical of Ni-G) is important in effective uptake and release of Li-ions in these materials. Source: ACS |
A Kansas State University researcher is developing more efficient ways to save costs, time and energy when creating nanomaterials and lithium-ion batteries.
Gurpreet Singh, assistant professor of mechanical and nuclear engineering, and his research team have published two recent articles on newer, cheaper and faster methods for creating nanomaterials that can be used for lithium-ion batteries. In the past year, Singh has published eight articles -- five of which involve lithium-ion battery research.
"We are exploring new methods for quick and cost-effective synthesis of two-dimensional materials for rechargeable battery applications," Singh said. "We are interested in this research because understanding lithium interaction with single-, double- and multiple-layer-thick materials will eventually allow us to design battery electrodes for practical applications. This includes batteries that show improved capacity, efficiency and longer life."
For the latest research, Singh's team created graphene films that are between two and 10 layers thick. Graphene is an atom-thick sheet of carbon. The researchers grew the graphene films on copper and nickel foils by quickly heating them in a furnace in the presence of controlled amounts of argon, hydrogen and methane gases. The team has been able to create these films in less than 30 minutes. Their work appears in the January issue of ACS-Applied Materials and Interfaces in an article titled "Synthesis of graphene films by rapid heating and quenching at ambient pressures and their electrochemical characterization."
The research is significant because the researchers created these graphene sheets by quickly heating and cooling the copper and nickel substrates at atmospheric pressures, meaning that scientists no longer need a vacuum to create few-layer-thick graphene films and can save energy, time and cost, Singh said.
The researchers used these graphene films to create the negative electrode of a lithium-ion cell and then studied the charge and discharge characteristics of this rechargeable battery. They found the graphene films grown on copper did not cycle the lithium ions and the battery capacity was negligible. But graphene grown on nickel showed improved performance because it was able to store and release lithium ions more efficiently.
"We believe that this behavior occurs because sheets of graphene on nickel are relatively thick near the grain boundaries and stacked in a well-defined manner -- called Bernal Stacking -- which provides multiple sites for easy uptake and release of lithium ions as the battery is discharged and charged," Singh said.
In a second research project, the researchers created tungsten disulfide nanosheets that were approximately 10 layers thick. Starting with bulk tungsten disulfide powder -- which is a type of dry lubricant used in the automotive industry -- the team was able to separate atomic layer thick sheets of tungsten disulfide in a strong acid solution. This simple method made it possible to produce sheets in large quantities. Much like graphene, tungsten disulfide also has a layered atomic structure, but the individual layers are three atoms thick.
The researchers found that these acid-treated tungsten disulfide sheets could also store and release lithium ions but in a different way. The lithium is stored through a conversion reaction in which tungsten disulfide dissociates to form tungsten and lithium sulfide as the cell is discharged. Unlike graphene, this reaction involves the transfer of at least two electrons per tungsten atom. This is important because researchers have long disregarded such compounds as battery anodes because of the difficulty associated with adding lithium to these materials, Singh said. It is only recently that the conversion reaction-based battery anodes have gained popularity.
"We also realize that tungsten disulfideis a heavy compound compared to state-of-the-art graphite used in current lithium-ion batteries," Singh said. "Therefore tungsten disulfide may not be an ideal electrode material for portable batteries."
The research appeared in a recent issue of the Journal of Physical Chemistry Letters in an article titled "Synthesis of surface-functionalized WS2 nanosheets and performance as Li-ion battery anodes."
Both projects are important because they can help scientists create nanomaterials in a cost-effective way. While many studies have focused on making graphene using low-pressure chemical processes, little research has been tried using rapid heating and cooling at atmospheric pressures, Singh said. Similarly, large quantities of single-layer and multiple-layer thick sheets of tungsten disulfide are needed for other applications.
"Interestingly, for most applications that involve this kind of battery research and corrosion prevention, films that are a few atoms thick are usually sufficient," Singh said. "Very high quality large area single-atom-thick films are not a necessity."
Other Kansas State University researchers involved in the projects include Romil Bhandavat and Lamuel David, both doctoral students in mechanical engineering, India, and Saksham Pahwa, a visiting undergraduate student, India. The graphene research involved University of Michigan researchers, including Zhaohui Zhong, assistant professor of electrical engineering and computer science, andGirish Kulkarni, doctoral candidate in electrical engineering.
Singh's work has been supported by the National Institute of Standards and Technology and the Kansas National Science Foundation Experimental Program to Stimulate Competitive Research program.
Singh plans future research to study how these layered nanomaterials can create better electrodes in the form of heterostructures, which are essentially three-dimensional stacked structures involving alternating layers of graphene and tungsten or molybdenum disulfide.
Source: Kansas State University
Additional Information:
Sunday, 13 January 2013
Peel-and-Stick Solar Cells: Devices could charge battery-powered products in the future
Engineerblogger
Jan 13, 2013
It may be possible soon to charge cell phones, change the tint on windows, or power small toys with peel-and-stick versions of solar cells, thanks to a partnership between Stanford University and the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL).
A scientific paper, “Peel and Stick: Fabricating Thin Film Solar Cells on Universal Substrates,” appears in the online version of Scientific Reports, a subsidiary of the British scientific journal Nature.
Peel-and-stick, or water-assisted transfer printing (WTP), technologies were developed by the Stanford group and have been used before for nanowire based electronics, but the Stanford-NREL partnership has conducted the first successful demonstration using actual thin film solar cells, NREL principal scientist Qi Wang said.
The university and NREL showed that thin-film solar cells less than one-micron thick can be removed from a silicon substrate used for fabrication by dipping them in water at room temperature. Then, after exposure to heat of about 90°C for a few seconds, they can attach to almost any surface.
Wang met Stanford’s Xiaolin Zheng at a conference last year where Wang gave a talk about solar cells and Zheng talked about her peel-and-stick technology. Zheng realized that NREL had the type of solar cells needed for her peel-and-stick project.
NREL’s cells could be made easily on Stanford’s peel off substrate. NREL’s amorphous silicon cells were fabricated on nickel-coated Si/SiO2 wafers. A thermal release tape attached to the top of the solar cell serves as a temporary transfer holder. An optional transparent protection layer is spin-casted in between the thermal tape and the solar cell to prevent contamination when the device is dipped in water. The result is a thin strip much like a bumper sticker: the user can peel off the handler and apply the solar cell directly to a surface.
“It’s been a quite successful collaboration,” Wang said. “We were able to peel it off nicely and test the cell both before and after. We found almost no degradation in performance due to the peel-off.”
Zheng said the partnership with NREL is the key for this successful work. “NREL has years of experience with thin film solar cells that allowed us to build upon their success,” Zheng said. “Qi Wang and (NREL engineer) William Nemeth are very valuable and efficient collaborators.”
Zheng said cells can be mounted to almost any surface because almost no fabrication is required on the final carrier substrates.
The cells’ ability to adhere to a universal substrate is unusual; most thin-film cells must be affixed to a special substrate. The peel-and-stick approach allows the use of flexible polymer substrates and high processing temperatures. The resulting flexible, lightweight, and transparent devices then can be integrated onto curved surfaces such as military helmets and portable electronics, transistors and sensors.
In the future, the collaborators will test peel-and-stick cells that are processed at even higher temperatures and offer more power.
Source: National Renewable Energy Laboratory (NREL)
Additional Information:
Jan 13, 2013
 |
| (a) As-fabricated TFSCs on the original Si/SiO2 wafer. (b) The TFSCs are peeled off from the Si/SiO2
wafer in a water bath at room temperature. (c) The peeled off TFSCs are
attached to a target substrate with adhesive agents. (d) The temporary
transfer holder is removed, and only the TFSCs are left on the target
substrate. Credit: Nature |
It may be possible soon to charge cell phones, change the tint on windows, or power small toys with peel-and-stick versions of solar cells, thanks to a partnership between Stanford University and the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL).
A scientific paper, “Peel and Stick: Fabricating Thin Film Solar Cells on Universal Substrates,” appears in the online version of Scientific Reports, a subsidiary of the British scientific journal Nature.
Peel-and-stick, or water-assisted transfer printing (WTP), technologies were developed by the Stanford group and have been used before for nanowire based electronics, but the Stanford-NREL partnership has conducted the first successful demonstration using actual thin film solar cells, NREL principal scientist Qi Wang said.
The university and NREL showed that thin-film solar cells less than one-micron thick can be removed from a silicon substrate used for fabrication by dipping them in water at room temperature. Then, after exposure to heat of about 90°C for a few seconds, they can attach to almost any surface.
Wang met Stanford’s Xiaolin Zheng at a conference last year where Wang gave a talk about solar cells and Zheng talked about her peel-and-stick technology. Zheng realized that NREL had the type of solar cells needed for her peel-and-stick project.
NREL’s cells could be made easily on Stanford’s peel off substrate. NREL’s amorphous silicon cells were fabricated on nickel-coated Si/SiO2 wafers. A thermal release tape attached to the top of the solar cell serves as a temporary transfer holder. An optional transparent protection layer is spin-casted in between the thermal tape and the solar cell to prevent contamination when the device is dipped in water. The result is a thin strip much like a bumper sticker: the user can peel off the handler and apply the solar cell directly to a surface.
“It’s been a quite successful collaboration,” Wang said. “We were able to peel it off nicely and test the cell both before and after. We found almost no degradation in performance due to the peel-off.”
Zheng said the partnership with NREL is the key for this successful work. “NREL has years of experience with thin film solar cells that allowed us to build upon their success,” Zheng said. “Qi Wang and (NREL engineer) William Nemeth are very valuable and efficient collaborators.”
Zheng said cells can be mounted to almost any surface because almost no fabrication is required on the final carrier substrates.
The cells’ ability to adhere to a universal substrate is unusual; most thin-film cells must be affixed to a special substrate. The peel-and-stick approach allows the use of flexible polymer substrates and high processing temperatures. The resulting flexible, lightweight, and transparent devices then can be integrated onto curved surfaces such as military helmets and portable electronics, transistors and sensors.
In the future, the collaborators will test peel-and-stick cells that are processed at even higher temperatures and offer more power.
Source: National Renewable Energy Laboratory (NREL)
Additional Information:
- “Peel and Stick: Fabricating Thin Film Solar Cells on Universal Substrates,” appears in the online version of Scientific Reports ("Peel-and-Stick: Fabricating Thin Film Solar Cell on Universal Substrates").
Saturday, 12 January 2013
Smarter infrastructure: Converting vibrations into electricity
Engineerblogger
Jan 12, 2013
A team from the Centre for Smart Infrastructure and Construction have developed a mechanical amplifier to convert ambient vibrations into electricity more effectively, which could be used to power wireless sensors for monitoring the structural health of roads, bridges and tunnels.
Undetected structural problems in aging infrastructure can be disastrous, such as the recent incident in the busy Sasago tunnel west of Tokyo. Nine people were killed when huge chunks of concrete began to fall from the roof of the tunnel, starting a fire and trapping people in their vehicles. Thankfully, such incidents are rare, but the ability to determine when structural problems may become a threat to public safety is a major priority for government and industry.
The Centre for Smart Infrastructure and Construction (CSIC) was established in 2011 to develop and commercialise new technologies designed to make smart infrastructure possible, primarily through the development of new sensor and data management technologies, which will enable continuous monitoring of our roads, tunnels and bridges.
A new device designed by researchers in the CSIC could allow this type of observations by converting the vibration experienced by structures into electricity, in order to power small remote monitoring devices in locations where access is limited, such as inside a tunnel or underneath a bridge.
“Wireless sensors are one way to better look after infrastructure, and it’s something that industry is interested in doing, but batteries are always the sticking point,” says Professor Kenichi Soga, who designed the device with Dr Ashwin Seshia and Yu Jia, a PhD student in Dr Seshia’s group. “It’s not the cost of the batteries that is the issue; it’s the cost of human power to replace the batteries.”
Since the devices are self-powered, there is no need to have individuals change the batteries on a regular basis, thereby decreasing cost to industry while enabling continuous remote monitoring in order to detect problems at an early stage.
Self-powered battery-less devices are not an entirely new concept: other energy harvesting principles are used to power digital wristwatches and handheld torches. Existing devices based on vibrational energy harvesting suffer from two key technical limitations, however: low output power density, and the mismatch between the narrow operational frequency bandwidth of conventional energy harvesters and the wideband nature of vibrations experienced by bridges, tunnels and roads.
The device developed by the CSIC team addresses these issues by basing their harvester on a phenomenon known as parametric resonance. The energy harvesting device can be realised as a micro-electromechanical system (MEMS) device, consisting of a micro-cantilever structure and a transducer. When force is applied to the cantilever perpendicular to the length instead of transversely, parametric resonance can be achieved, generating more energy from the same amount of vibration.
The MEMS device provides the added advantage of using batch manufacturing principles common to the semiconductor industry, potentially enabling low-cost battery replacement, large-scale volume production and co-integration with sensors and interface electronics to realise truly autonomous smart sensor nodes: a challenge that the CSIC team are seeking to address in the context of developing innovative monitoring technologies for large-scale built infrastructure.
Prototype versions of MEMS and macro-scale devices based on these principles have demonstrated a significantly improved power output and a wider operational bandwidth relative to current state-of-the-art devices. Preliminary results on a MEMS prototype were presented at the PowerMEMS conference in Atlanta in December. The device is being commercialised by Cambridge Enterprise, the University’s technology transfer office.
In addition to applications in the construction industry, the device also has potential applications such as powering wearable medical devices or extending the life of batteries in mobile phones.
CSIC was established in 2011, and brings together researchers from the Department of Engineering, along with colleagues from the Department of Architecture, the Computer Laboratory, the Judge Business School and Cambridge Enterprise.
Source: University of Cambridge
Jan 12, 2013
 |
| Tunnel Credit: stopthegears, via Flickr creative commons |
A team from the Centre for Smart Infrastructure and Construction have developed a mechanical amplifier to convert ambient vibrations into electricity more effectively, which could be used to power wireless sensors for monitoring the structural health of roads, bridges and tunnels.
Undetected structural problems in aging infrastructure can be disastrous, such as the recent incident in the busy Sasago tunnel west of Tokyo. Nine people were killed when huge chunks of concrete began to fall from the roof of the tunnel, starting a fire and trapping people in their vehicles. Thankfully, such incidents are rare, but the ability to determine when structural problems may become a threat to public safety is a major priority for government and industry.
The Centre for Smart Infrastructure and Construction (CSIC) was established in 2011 to develop and commercialise new technologies designed to make smart infrastructure possible, primarily through the development of new sensor and data management technologies, which will enable continuous monitoring of our roads, tunnels and bridges.
A new device designed by researchers in the CSIC could allow this type of observations by converting the vibration experienced by structures into electricity, in order to power small remote monitoring devices in locations where access is limited, such as inside a tunnel or underneath a bridge.
“Wireless sensors are one way to better look after infrastructure, and it’s something that industry is interested in doing, but batteries are always the sticking point,” says Professor Kenichi Soga, who designed the device with Dr Ashwin Seshia and Yu Jia, a PhD student in Dr Seshia’s group. “It’s not the cost of the batteries that is the issue; it’s the cost of human power to replace the batteries.”
Since the devices are self-powered, there is no need to have individuals change the batteries on a regular basis, thereby decreasing cost to industry while enabling continuous remote monitoring in order to detect problems at an early stage.
Self-powered battery-less devices are not an entirely new concept: other energy harvesting principles are used to power digital wristwatches and handheld torches. Existing devices based on vibrational energy harvesting suffer from two key technical limitations, however: low output power density, and the mismatch between the narrow operational frequency bandwidth of conventional energy harvesters and the wideband nature of vibrations experienced by bridges, tunnels and roads.
The device developed by the CSIC team addresses these issues by basing their harvester on a phenomenon known as parametric resonance. The energy harvesting device can be realised as a micro-electromechanical system (MEMS) device, consisting of a micro-cantilever structure and a transducer. When force is applied to the cantilever perpendicular to the length instead of transversely, parametric resonance can be achieved, generating more energy from the same amount of vibration.
The MEMS device provides the added advantage of using batch manufacturing principles common to the semiconductor industry, potentially enabling low-cost battery replacement, large-scale volume production and co-integration with sensors and interface electronics to realise truly autonomous smart sensor nodes: a challenge that the CSIC team are seeking to address in the context of developing innovative monitoring technologies for large-scale built infrastructure.
Prototype versions of MEMS and macro-scale devices based on these principles have demonstrated a significantly improved power output and a wider operational bandwidth relative to current state-of-the-art devices. Preliminary results on a MEMS prototype were presented at the PowerMEMS conference in Atlanta in December. The device is being commercialised by Cambridge Enterprise, the University’s technology transfer office.
In addition to applications in the construction industry, the device also has potential applications such as powering wearable medical devices or extending the life of batteries in mobile phones.
CSIC was established in 2011, and brings together researchers from the Department of Engineering, along with colleagues from the Department of Architecture, the Computer Laboratory, the Judge Business School and Cambridge Enterprise.
Source: University of Cambridge
How to treat heat like light: Using nanoparticle alloys allows heat to be focused or reflected just like electromagnetic waves
Engineerblogger
Jan 12, 2012
An MIT researcher has developed a technique that provides a new way of manipulating heat, allowing it to be controlled much as light waves can be manipulated by lenses and mirrors.
The approach relies on engineered materials consisting of nanostructured semiconductor alloy crystals. Heat is a vibration of matter — technically, a vibration of the atomic lattice of a material — just as sound is. Such vibrations can also be thought of as a stream of phonons — a kind of “virtual particle” that is analogous to the photons that carry light. The new approach is similar to recently developed photonic crystals that can control the passage of light, and phononic crystals that can do the same for sound.
The spacing of tiny gaps in these materials is tuned to match the wavelength of the heat phonons, explains Martin Maldovan, a research scientist in MIT’s Department of Materials Science and Engineering and author of a paper on the new findings published Jan. 11 in the journal Physical Review Letters.
“It’s a completely new way to manipulate heat,” Maldovan says. Heat differs from sound, he explains, in the frequency of its vibrations: Sound waves consist of lower frequencies (up to the kilohertz range, or thousands of vibrations per second), while heat arises from higher frequencies (in the terahertz range, or trillions of vibrations per second).
In order to apply the techniques already developed to manipulate sound, Maldovan’s first step was to reduce the frequency of the heat phonons, bringing it closer to the sound range. He describes this as “hypersonic heat.”
“Phonons for sound can travel for kilometers,” Maldovan says — which is why it’s possible to hear noises from very far away. “But phonons of heat only travel for nanometers [billionths of a meter]. That’s why you couldn’t hear heat even with ears responding to terahertz frequencies.”
Heat also spans a wide range of frequencies, he says, while sound spans a single frequency. So, to address that, Maldovan says, “the first thing we did is reduce the number of frequencies of heat, and we made them lower,” bringing these frequencies down into the boundary zone between heat and sound. Making alloys of silicon that incorporate nanoparticles of germanium in a particular size range accomplished this lowering of frequency, he says.
Reducing the range of frequencies was also accomplished by making a series of thin films of the material, so that scattering of phonons would take place at the boundaries. This ends up concentrating most of the heat phonons within a relatively narrow “window” of frequencies.
Following the application of these techniques, more than 40 percent of the total heat flow is concentrated within a hypersonic range of 100 to 300 gigahertz, and most of the phonons align in a narrow beam, instead of moving in every direction.
As a result, this beam of narrow-frequency phonons can be manipulated using phononic crystals similar to those developed to control sound phonons. Because these crystals are now being used to control heat instead, Maldovan refers to them as “thermocrystals,” a new category of materials.
These thermocrystals might have a wide range of applications, he suggests, including in improved thermoelectric devices, which convert differences of temperature into electricity. Such devices transmit electricity freely while strictly controlling the flow of heat — tasks that the thermocrystals could accomplish very effectively, Maldovan says.
Most conventional materials allow heat to travel in all directions, like ripples expanding outward from a pebble dropped in a pond; thermocrystals could instead produce the equivalent of those ripples only moving out in a single direction, Maldovan says. The crystals could also be used to create thermal diodes: materials in which heat can pass in one direction, but not in the reverse direction. Such a one-way heat flow could be useful in energy-efficient buildings in hot and cold climates.
Other variations of the material could be used to focus heat — much like focusing light with a lens — to concentrate it in a small area. Another intriguing possibility is thermal cloaking, Maldovan says: materials that prevent detection of heat, just as recently developed metamaterials can create “invisibility cloaks” to shield objects from detection by visible light or microwaves.
Rama Venkatasubramanian, senior research director at the Center for Solid State Energetics at RTI International in North Carolina, says this is “an interesting approach to control the various frequencies of the phonon spectra that conduct heat in a solid-state material.”
The modeling used to develop this new system “needs to be further developed,” Venkatasubramanian adds. “The theory of what wavelengths of phonons, and at what temperatures, contribute to how much heat transport is a complex problem even in simpler materials, let alone nanostructured materials, and these will have to be factored in — so this paper will trigger more interest and study in that direction.”
Source: MIT
Jan 12, 2012
 |
| Thermal lattices, shown here, are one possible application of the newly developed thermocrystals. In these structures, where precisely spaced air gaps (dark circles) control the flow of heat, thermal energy can be "pinned" in place by defects introduced into the structure (colored areas). Illustration courtesy of Martin Maldovan |
An MIT researcher has developed a technique that provides a new way of manipulating heat, allowing it to be controlled much as light waves can be manipulated by lenses and mirrors.
The approach relies on engineered materials consisting of nanostructured semiconductor alloy crystals. Heat is a vibration of matter — technically, a vibration of the atomic lattice of a material — just as sound is. Such vibrations can also be thought of as a stream of phonons — a kind of “virtual particle” that is analogous to the photons that carry light. The new approach is similar to recently developed photonic crystals that can control the passage of light, and phononic crystals that can do the same for sound.
The spacing of tiny gaps in these materials is tuned to match the wavelength of the heat phonons, explains Martin Maldovan, a research scientist in MIT’s Department of Materials Science and Engineering and author of a paper on the new findings published Jan. 11 in the journal Physical Review Letters.
“It’s a completely new way to manipulate heat,” Maldovan says. Heat differs from sound, he explains, in the frequency of its vibrations: Sound waves consist of lower frequencies (up to the kilohertz range, or thousands of vibrations per second), while heat arises from higher frequencies (in the terahertz range, or trillions of vibrations per second).
In order to apply the techniques already developed to manipulate sound, Maldovan’s first step was to reduce the frequency of the heat phonons, bringing it closer to the sound range. He describes this as “hypersonic heat.”
“Phonons for sound can travel for kilometers,” Maldovan says — which is why it’s possible to hear noises from very far away. “But phonons of heat only travel for nanometers [billionths of a meter]. That’s why you couldn’t hear heat even with ears responding to terahertz frequencies.”
Heat also spans a wide range of frequencies, he says, while sound spans a single frequency. So, to address that, Maldovan says, “the first thing we did is reduce the number of frequencies of heat, and we made them lower,” bringing these frequencies down into the boundary zone between heat and sound. Making alloys of silicon that incorporate nanoparticles of germanium in a particular size range accomplished this lowering of frequency, he says.
Reducing the range of frequencies was also accomplished by making a series of thin films of the material, so that scattering of phonons would take place at the boundaries. This ends up concentrating most of the heat phonons within a relatively narrow “window” of frequencies.
Following the application of these techniques, more than 40 percent of the total heat flow is concentrated within a hypersonic range of 100 to 300 gigahertz, and most of the phonons align in a narrow beam, instead of moving in every direction.
As a result, this beam of narrow-frequency phonons can be manipulated using phononic crystals similar to those developed to control sound phonons. Because these crystals are now being used to control heat instead, Maldovan refers to them as “thermocrystals,” a new category of materials.
These thermocrystals might have a wide range of applications, he suggests, including in improved thermoelectric devices, which convert differences of temperature into electricity. Such devices transmit electricity freely while strictly controlling the flow of heat — tasks that the thermocrystals could accomplish very effectively, Maldovan says.
Most conventional materials allow heat to travel in all directions, like ripples expanding outward from a pebble dropped in a pond; thermocrystals could instead produce the equivalent of those ripples only moving out in a single direction, Maldovan says. The crystals could also be used to create thermal diodes: materials in which heat can pass in one direction, but not in the reverse direction. Such a one-way heat flow could be useful in energy-efficient buildings in hot and cold climates.
Other variations of the material could be used to focus heat — much like focusing light with a lens — to concentrate it in a small area. Another intriguing possibility is thermal cloaking, Maldovan says: materials that prevent detection of heat, just as recently developed metamaterials can create “invisibility cloaks” to shield objects from detection by visible light or microwaves.
Rama Venkatasubramanian, senior research director at the Center for Solid State Energetics at RTI International in North Carolina, says this is “an interesting approach to control the various frequencies of the phonon spectra that conduct heat in a solid-state material.”
The modeling used to develop this new system “needs to be further developed,” Venkatasubramanian adds. “The theory of what wavelengths of phonons, and at what temperatures, contribute to how much heat transport is a complex problem even in simpler materials, let alone nanostructured materials, and these will have to be factored in — so this paper will trigger more interest and study in that direction.”
Source: MIT
Good vibrations: Scientists recently developed a new microvibration excitation device
Engineerblogger
Jan 12, 2013
NPL scientists recently developed a new microvibration excitation device, which is currently under test at the European Space Agency (ESA) space test centre at ESTEC in Noordwijk, Holland.
The 'little shaker' device was produced as part of a technology research project for ESA to develop a prototype universal reference excitation unit which can be used to validate the performance of all kind of microvibration test facilities, traceable to ISO17025 levels of confidence and which can be deployed to perform inter facility comparison measurements.
The device is about the size of a shoe-box and generates small forces and torques (µN/µNm to single digit N/Nm range) at relatively low frequency (0.05 Hz to 10 Hz) in a controlled manner via reaction force against a moving mass. It can create force and torque along or about a single axis, and be repositioned in any orientation, to allow six-degree-of-freedom forces to be generated. The device is unique because there are currently no comparable means of producing highly repeatable forces and torques of this low magnitude in such a small, compact and portable mechanism.
Testing at the ESTEC space test center involved placing the device on Reaction Wheel Characterization Facility platform, activating it to create sinusoidal forces and moments in various orientations, and comparing the generated forces with those measured by the ESTEC facility.
Preliminary results are excellent and ESA now has a prototype device it can take to other facilities that will produce an identical drive signal, to allow comparisons of measurement results between facilities.
NPL was a natural partner for ESA on this project due to previous successful collaborations with challenging micro-thrust measurements. Additionally, NPL's role as the UK's National Measurement Institute provides confidence and experience in measurements traceable to primary standards and will be critical in allowing ESA to accredit their microvibration facility to the ISO 17025 standard in the future.
Source: NPL
Additional Information:
Jan 12, 2013
NPL scientists recently developed a new microvibration excitation device, which is currently under test at the European Space Agency (ESA) space test centre at ESTEC in Noordwijk, Holland.
 |
| The NPL excitation unit mounted on the ESA Reaction Wheel Characterization Facility |
The 'little shaker' device was produced as part of a technology research project for ESA to develop a prototype universal reference excitation unit which can be used to validate the performance of all kind of microvibration test facilities, traceable to ISO17025 levels of confidence and which can be deployed to perform inter facility comparison measurements.
The device is about the size of a shoe-box and generates small forces and torques (µN/µNm to single digit N/Nm range) at relatively low frequency (0.05 Hz to 10 Hz) in a controlled manner via reaction force against a moving mass. It can create force and torque along or about a single axis, and be repositioned in any orientation, to allow six-degree-of-freedom forces to be generated. The device is unique because there are currently no comparable means of producing highly repeatable forces and torques of this low magnitude in such a small, compact and portable mechanism.
Testing at the ESTEC space test center involved placing the device on Reaction Wheel Characterization Facility platform, activating it to create sinusoidal forces and moments in various orientations, and comparing the generated forces with those measured by the ESTEC facility.
Preliminary results are excellent and ESA now has a prototype device it can take to other facilities that will produce an identical drive signal, to allow comparisons of measurement results between facilities.
NPL was a natural partner for ESA on this project due to previous successful collaborations with challenging micro-thrust measurements. Additionally, NPL's role as the UK's National Measurement Institute provides confidence and experience in measurements traceable to primary standards and will be critical in allowing ESA to accredit their microvibration facility to the ISO 17025 standard in the future.
Source: NPL
Additional Information:
- Find out more about NPL's Dimensional research
Monday, 7 January 2013
Ford 1.0-Liter EcoBoost Engine Sets the Standard for Smoothness and Quietness in Small Engines
Engineerblogger
Jan 7, 2013
Start up Ford’s patented new 1.0-liter three-cylinder EcoBoost® engine and chances are you’ll have to look at the tachometer to verify that the engine is running.
Ford engineers always knew they could build a powerful, fuel-efficient three-cylinder engine. The real engineering magic would be solving the problem that has often sunk previous three-cylinder automobile engines – conquering the unpleasant vibrations that come from having an odd number of cylinders under the hood.
For Ford’s new three-cylinder engine to be successful, it would have to be a no-compromise engine. It could not force customers to choose between performance versus economy or responsiveness versus smoothness. It had to deliver it all and it had to be affordable.
The traditional way of reducing shaking forces in small-displacement engines is to install a counter-rotating balance shaft inside the motor that cancels out most vibrations. But the problem with a balance shaft, explains Andy Delicata, Ford of Europe manager of Powertrain Noise, Vibration and Harshness, is that it is heavy, expensive, and it reduces fuel economy.
The 1.0-liter’s NVH engineering team, led by Delicata at Ford Technical Centres in Dunton and Dagenham, England, attacked the problem by focusing on two areas – the engine’s front pulley and rear flywheel, and the mounting system that connects the powertrain with the car’s body.
The pulley and flywheel are unbalanced with weights that are placed precisely to counteract the natural shaking forces of the engine and drive the energy in a less sensitive direction. The engine mounts are designed to decouple as well as absorb the engine’s shaking forces, Delicata explained.
The result is one of the smoothest and quietest engines in Ford’s global lineup. “We like to compare the refinement of the 1.0-liter EcoBoost engine with what you would typically experience in a vehicle two or three classes up from Fiesta and Focus,” said Delicata.
The smoothness of the engine is complemented by class-leading quietness. Engineers in Dunton and Dagenham attacked engine noise at its many sources.
For instance, a super-compact, highly stiff cast-iron block structure and an integrated engine mounting bracket are crucial in absorbing noise energy. In addition to immersing the engine’s toothed rubber timing belts in oil, isolated fuel injectors electronically controlled for soft landing and a foam-covered engine collectively help keep noise and vibration from reaching the driver.
The 1.0-liter EcoBoost engine is off to a fast start in Europe. Since its launch in March in the Focus, the 1.0-liter EcoBoost engine has won four major international awards. In the Focus, the 1.0-liter engine accounts for about 30 percent of sales, no small feat in a part of the world where the diesel engine is king.
The 1.0-liter is just now launching in B-MAX and C-MAX, and will be available in North America next year in the redesigned 2014 Ford Fiesta.
Source: Ford Motor Company
Additional Information:
Jan 7, 2013
 |
| Ford CEO Alan Mulally kissing 1.0-liter EcoBoost engine |
- Innovative engine mounts, flywheel and pulley in the new 1.0-liter Ford EcoBoost® engine combine to dramatically reduce the vibrations that are inherent in three-cylinder engines
- Super-stiff block, isolated fuel injectors and oil-immersed timing belts help make 1.0-liter EcoBoost engine one of Ford’s quietest engines
- 1.0-liter EcoBoost engine debuts in North America in the redesigned 2014 Ford Fiesta
Start up Ford’s patented new 1.0-liter three-cylinder EcoBoost® engine and chances are you’ll have to look at the tachometer to verify that the engine is running.
Ford engineers always knew they could build a powerful, fuel-efficient three-cylinder engine. The real engineering magic would be solving the problem that has often sunk previous three-cylinder automobile engines – conquering the unpleasant vibrations that come from having an odd number of cylinders under the hood.
For Ford’s new three-cylinder engine to be successful, it would have to be a no-compromise engine. It could not force customers to choose between performance versus economy or responsiveness versus smoothness. It had to deliver it all and it had to be affordable.
The traditional way of reducing shaking forces in small-displacement engines is to install a counter-rotating balance shaft inside the motor that cancels out most vibrations. But the problem with a balance shaft, explains Andy Delicata, Ford of Europe manager of Powertrain Noise, Vibration and Harshness, is that it is heavy, expensive, and it reduces fuel economy.
The 1.0-liter’s NVH engineering team, led by Delicata at Ford Technical Centres in Dunton and Dagenham, England, attacked the problem by focusing on two areas – the engine’s front pulley and rear flywheel, and the mounting system that connects the powertrain with the car’s body.
The pulley and flywheel are unbalanced with weights that are placed precisely to counteract the natural shaking forces of the engine and drive the energy in a less sensitive direction. The engine mounts are designed to decouple as well as absorb the engine’s shaking forces, Delicata explained.
The result is one of the smoothest and quietest engines in Ford’s global lineup. “We like to compare the refinement of the 1.0-liter EcoBoost engine with what you would typically experience in a vehicle two or three classes up from Fiesta and Focus,” said Delicata.
The smoothness of the engine is complemented by class-leading quietness. Engineers in Dunton and Dagenham attacked engine noise at its many sources.
For instance, a super-compact, highly stiff cast-iron block structure and an integrated engine mounting bracket are crucial in absorbing noise energy. In addition to immersing the engine’s toothed rubber timing belts in oil, isolated fuel injectors electronically controlled for soft landing and a foam-covered engine collectively help keep noise and vibration from reaching the driver.
The 1.0-liter EcoBoost engine is off to a fast start in Europe. Since its launch in March in the Focus, the 1.0-liter EcoBoost engine has won four major international awards. In the Focus, the 1.0-liter engine accounts for about 30 percent of sales, no small feat in a part of the world where the diesel engine is king.
The 1.0-liter is just now launching in B-MAX and C-MAX, and will be available in North America next year in the redesigned 2014 Ford Fiesta.
Source: Ford Motor Company
Additional Information:
Leah Buechley: How to “sketch” with electronics
Engineerblogger
Jan 6, 2012
Designing electronics is generally cumbersome and expensive -- or was, until Leah Buechley and her team at MIT developed tools to treat electronics just like paper and pen. In this talk from TEDYouth 2011, Buechley shows some of her charming designs, like a paper piano you can sketch and then play.
Leah Buechley is an MIT electronics designer who mixes high and low tech to create smart and playful results.
Source: TED
Additional Information:
Jan 6, 2012
Designing electronics is generally cumbersome and expensive -- or was, until Leah Buechley and her team at MIT developed tools to treat electronics just like paper and pen. In this talk from TEDYouth 2011, Buechley shows some of her charming designs, like a paper piano you can sketch and then play.
Leah Buechley is an MIT electronics designer who mixes high and low tech to create smart and playful results.
Source: TED
Additional Information:
Saturday, 5 January 2013
Building a better machine: Students use creativity to improve the heat engine
Engineerblogger
Jan 4, 2012
When Roman Berens signed up for the “Physics and Applied Physics Research Freshman” Seminar, he wasn’t sure what to expect.
“Initially, I really had no idea what it was about,” he said. “But I’m majoring in physics, so I thought having lab experience would be really valuable.”
Berens and other freshmen in the seminar discussed their research at a presentation at the Rowland Institute on Dec. 12. Using a handmade, laboratory-scale, Sterling heat engine, the team of students was able to generate enough electricity to power several light-emitting diodes, or LEDs, and a laptop computer.
“I’m amazed and invigorated by what our freshmen are capable of,” said Jene Golovchenko, Rumford Professor of Physics and Gordon McKay Professor of Applied Physics, and professor to the freshman seminar. “This year’s class has a wonderful collection of students who were admitted by interview to assure they were ready to take advantage of the high level of support provided them by the Rowland Institute. They are all prime candidates to concentrate in either in physics or SEAS,” the School of Engineering and Applied Sciences.
The seminar challenged students to study and improve upon the Sterling heat engine constructed by last year’s seminar students. Participants were tasked to improve on the existing model, turning it into a scientific instrument — embodying the laws of classical mechanics and thermodynamics.
To read more click here...
Jan 4, 2012
 |
Photos by Kris Snibbe/Harvard Staff Photographer
Elizabeth Kane looks at a Sterling heat engine model that
eliminates the standard piston system. The presentation was part of the
“Physics and Applied Physics Research Freshman Seminar." The seminar
challenged students to study and improve upon the Sterling heat engine
constructed by last year’s seminar students.
|
When Roman Berens signed up for the “Physics and Applied Physics Research Freshman” Seminar, he wasn’t sure what to expect.
“Initially, I really had no idea what it was about,” he said. “But I’m majoring in physics, so I thought having lab experience would be really valuable.”
Berens and other freshmen in the seminar discussed their research at a presentation at the Rowland Institute on Dec. 12. Using a handmade, laboratory-scale, Sterling heat engine, the team of students was able to generate enough electricity to power several light-emitting diodes, or LEDs, and a laptop computer.
“I’m amazed and invigorated by what our freshmen are capable of,” said Jene Golovchenko, Rumford Professor of Physics and Gordon McKay Professor of Applied Physics, and professor to the freshman seminar. “This year’s class has a wonderful collection of students who were admitted by interview to assure they were ready to take advantage of the high level of support provided them by the Rowland Institute. They are all prime candidates to concentrate in either in physics or SEAS,” the School of Engineering and Applied Sciences.
The seminar challenged students to study and improve upon the Sterling heat engine constructed by last year’s seminar students. Participants were tasked to improve on the existing model, turning it into a scientific instrument — embodying the laws of classical mechanics and thermodynamics.
To read more click here...
How a computer game could radically alter manufacturing
Engineerblogger
Jan 4, 2013
Here at The Engineer we’re used to explaining difficult concepts, whether it’s nuclear fusion or spintronics (actually I’m still not sure about that one). It helps that we have a receptive and enthusiastic audience and are tackling subject material that is usually instantly exciting.
But what if you had to explain something with less obvious appeal to people who think you might be wasting their time, for example, a complex new manufacturing business model to a group of sceptical bean counters? It’s probably not a conversation you’d want to have at a dinner party.
The answer to this might be to make the explanation into a game, according to one research group at least. Make the process fun, entertaining and engaging, and the audience might be more likely to understand and remember the concept, and perhaps even become more enthusiastic about it.
A team led by Aston University Business School are about to do just this by starting a five-year research project on the gamification of explaining servitisation. Now comes the bit where I explain what this boring and complicated-sounding concept actually is.
A product service system (PSS) is a business model where a firm offers both products and services. Rolls-Royce, for example, is well known for earning around 50 per cent of its revenue through service and support contracts, providing things such as maintenance and advice to customers that also buy its goods. Simply put, servitisation is when a straightforward manufacturing company adopts this model.
Particularly in developed marketplaces and economies, servitisation offers companies a chance to make more money than they would simply by selling products and competing against other manufacturers. Described like this, it sounds rather simple and very attractive. But making it a reality is a far more complex procedure with many barriers, and so servitisation of manufacturing firms has been slow.
Prof Tim Baines of Aston University argues that one of the biggest barriers to adoption of PSS is just explaining how the process of servitisation works. ‘To try to get those ideas across to someone in a manufacturing company in five or 10 minutes in a way that makes sense to them is quite challenging,’ he says.
This is where he believes gamification could come in. This is another slightly off-putting piece of jargon that basically means turning a process into a game. It’s not a new concept but has found growing popularity in recent years thanks to the growth of the internet and smartphones. There are any number of websites and apps that encourage you to do something by making it a game and rewarding you in some for participation.
For example, if you want to get fit but struggle to find the motivation, an app on your phone can monitor your progress to give you encouragement, telling you how many calories you’ve burnt or giving you badges for completing certain levels. One app even asks you to image you’re being chased by zombies and the only way to escape them is to run to a certain place.
But how will this work for explaining servitisation? Baines is planning to work with the Serious Games Institute at Coventry University and Sheffield’s Advanced Manufacturing Research Centre to create a computer simulation of a business adopting PSS. Companies, including Ford and Xerox, will then be brought in to test the game. ‘One of the big barriers is understanding, getting across the basic ideas and the language used, an appreciation of what it can actually mean,’ says Baines.
‘We’ll create a demonstration first of all so that we can communicate to the gaming community what we’re trying to do. The big hurdle is translating between these two communities, explaining to the gaming community what it is that we’re trying to model and them explaining to us what makes an engaging game. We’ve got to try to find the middle ground and from that we’ll create the basics of the game.’
It would be easy to write this concept of gamification off as a fad or a buzzword. For one thing, it doesn’t sound like the most fun idea for a game but, then again, there have been whole series of popular computer games designed around simulating real-life industries (Sim City, for example). And this won’t be the first time games are used to explain manufacturing concepts. Team games have been used before to demonstrate and introduce Western manufacturers to the Japanese-originated ideas of lean manufacturing.
Perhaps it will take more than a computer game to persuade companies to adopt dramatically different business models, but Baines hopes the game will do more than just change individual’s minds. ‘I would like it to be something quite pervasive that people inside the organisation become aware of and have a go at it, and for the top managers to hear about it not just from academics but also from people within the organisation who get to know about this thing called servitisation from playing the game.’
The game will also serve as a way for academics to further study servitisation so they can better understand the barriers to adopting PSS when it is attempted by real companies.
With gamification spreading even into business management techniques, it’s interesting to consider how else it could be used in manufacturing or other parts of the economy. Perhaps games could become a more common sight at work, motivating people to complete tasks or reach certain levels of achievement. On the other hand, you could argue we already run such a reward system. It’s called getting paid.
Source: The Engineer
Jan 4, 2013
Here at The Engineer we’re used to explaining difficult concepts, whether it’s nuclear fusion or spintronics (actually I’m still not sure about that one). It helps that we have a receptive and enthusiastic audience and are tackling subject material that is usually instantly exciting.
But what if you had to explain something with less obvious appeal to people who think you might be wasting their time, for example, a complex new manufacturing business model to a group of sceptical bean counters? It’s probably not a conversation you’d want to have at a dinner party.
The answer to this might be to make the explanation into a game, according to one research group at least. Make the process fun, entertaining and engaging, and the audience might be more likely to understand and remember the concept, and perhaps even become more enthusiastic about it.
A team led by Aston University Business School are about to do just this by starting a five-year research project on the gamification of explaining servitisation. Now comes the bit where I explain what this boring and complicated-sounding concept actually is.
A product service system (PSS) is a business model where a firm offers both products and services. Rolls-Royce, for example, is well known for earning around 50 per cent of its revenue through service and support contracts, providing things such as maintenance and advice to customers that also buy its goods. Simply put, servitisation is when a straightforward manufacturing company adopts this model.
Particularly in developed marketplaces and economies, servitisation offers companies a chance to make more money than they would simply by selling products and competing against other manufacturers. Described like this, it sounds rather simple and very attractive. But making it a reality is a far more complex procedure with many barriers, and so servitisation of manufacturing firms has been slow.
Prof Tim Baines of Aston University argues that one of the biggest barriers to adoption of PSS is just explaining how the process of servitisation works. ‘To try to get those ideas across to someone in a manufacturing company in five or 10 minutes in a way that makes sense to them is quite challenging,’ he says.
This is where he believes gamification could come in. This is another slightly off-putting piece of jargon that basically means turning a process into a game. It’s not a new concept but has found growing popularity in recent years thanks to the growth of the internet and smartphones. There are any number of websites and apps that encourage you to do something by making it a game and rewarding you in some for participation.
For example, if you want to get fit but struggle to find the motivation, an app on your phone can monitor your progress to give you encouragement, telling you how many calories you’ve burnt or giving you badges for completing certain levels. One app even asks you to image you’re being chased by zombies and the only way to escape them is to run to a certain place.
But how will this work for explaining servitisation? Baines is planning to work with the Serious Games Institute at Coventry University and Sheffield’s Advanced Manufacturing Research Centre to create a computer simulation of a business adopting PSS. Companies, including Ford and Xerox, will then be brought in to test the game. ‘One of the big barriers is understanding, getting across the basic ideas and the language used, an appreciation of what it can actually mean,’ says Baines.
‘We’ll create a demonstration first of all so that we can communicate to the gaming community what we’re trying to do. The big hurdle is translating between these two communities, explaining to the gaming community what it is that we’re trying to model and them explaining to us what makes an engaging game. We’ve got to try to find the middle ground and from that we’ll create the basics of the game.’
It would be easy to write this concept of gamification off as a fad or a buzzword. For one thing, it doesn’t sound like the most fun idea for a game but, then again, there have been whole series of popular computer games designed around simulating real-life industries (Sim City, for example). And this won’t be the first time games are used to explain manufacturing concepts. Team games have been used before to demonstrate and introduce Western manufacturers to the Japanese-originated ideas of lean manufacturing.
Perhaps it will take more than a computer game to persuade companies to adopt dramatically different business models, but Baines hopes the game will do more than just change individual’s minds. ‘I would like it to be something quite pervasive that people inside the organisation become aware of and have a go at it, and for the top managers to hear about it not just from academics but also from people within the organisation who get to know about this thing called servitisation from playing the game.’
The game will also serve as a way for academics to further study servitisation so they can better understand the barriers to adopting PSS when it is attempted by real companies.
With gamification spreading even into business management techniques, it’s interesting to consider how else it could be used in manufacturing or other parts of the economy. Perhaps games could become a more common sight at work, motivating people to complete tasks or reach certain levels of achievement. On the other hand, you could argue we already run such a reward system. It’s called getting paid.
Source: The Engineer
Jumping droplets help heat transfer
Engineerblogger
Jan 4, 2013
Many industrial plants depend on water vapor condensing on metal plates: In power plants, the resulting water is then returned to a boiler to be vaporized again; in desalination plants, it yields a supply of clean water. The efficiency of such plants depends crucially on how easily droplets of water can form on these metal plates, or condensers, and how easily they fall away, leaving room for more droplets to form.
The key to improving the efficiency of such plants is to increase the condensers’ heat-transfer coefficient — a measure of how readily heat can be transferred away from those surfaces, explains Nenad Miljkovic, a doctoral student in mechanical engineering at MIT. As part of his thesis research, he and colleagues have done just that: designing, making and testing a coated surface with nanostructured patterns that greatly increase the heat-transfer coefficient.
The results of that work have been published in the journal Nano Letters, in a paper co-authored by Miljkovic, mechanical engineering associate professor Evelyn Wang, and five other researchers from the Device Research Lab (DRL) in MIT’s mechanical engineering department.
On a typical, flat-plate condenser, water vapor condenses to form a liquid film on the surface, drastically reducing the condenser’s ability to collect more water until gravity drains the film. “It acts as a barrier to heat transfer,” Miljkovic says. He and other researchers have focused on ways of encouraging water to bead up into droplets that then fall away from the surface, allowing more rapid water removal.
“The way to remove the thermal barrier is to remove [the droplets] as quickly as possible,” he says. Many researchers have studied ways of doing this by creating hydrophobic surfaces, either through chemical treatment or through surface patterning. But Miljkovic and his colleagues have now taken this a step further by making scalable surfaces with nanoscale features that barely touch the droplets.
The result: Droplets don’t just fall from the surface, but actually jump away from it, increasing the efficiency of the process. The energy released as tiny droplets merge to form larger ones is enough to propel the droplets upward from the surface, meaning the removal of droplets doesn’t depend solely on gravity.
Other researchers have worked on nanopatterned surfaces to induce such jumping, but these have tended to be complex and expensive to manufacture, usually requiring a clean-room environment. Those approaches also require flat surfaces, not the tubing or other shapes often used in condensers. Finally, prior research has not tested the enhanced heat transfer predicted for these types of surfaces.
In a paper published early in 2012, the MIT researchers showed that droplet shape is important to enhanced heat transfer. “Now, we’ve gone a step further,” Miljkovic says, “developing a surface that favors these kinds of droplets, while being highly scalable and easy to manufacture. Furthermore, we’ve actually been able to experimentally measure the heat-transfer enhancement.”
The patterning is done, Miljkovic says, using a simple wet-oxidation process right on the surface that can be applied to the copper tubes and plates commonly used in commercial power plants.
The nanostructured pattern itself is made of copper oxide and actually forms on top of the copper tubing. The process produces a surface that resembles a bed of tiny, pointed leaves sticking up from the surface; these nanoscale points minimize contact between the droplets and the surface, making release easier.
Not only can the nanostructured patterns be made and applied under room-temperature conditions, but the growth process naturally stops itself. “It’s a self-limiting reaction,” Miljkovic says, “whether you put it in [the treatment solution] for two minutes or two hours.”
After the leaflike pattern is created, a hydrophobic coating is applied when a vapor solution bonds itself to the patterned surface without significantly altering its shape. The team’s experiments showed that the efficiency of heat transfer using these treated surfaces could be increased by 30 percent, compared to today’s best hydrophobic condensing surfaces.
That means, Miljkovic says, that the process lends itself to retrofitting thousands of power plants already in operation around the world. The technology could also be useful for other processes where heat transfer is important, such as in dehumidifiers and for heating and cooling systems for buildings, the authors say.
Challenges for this approach remain, Miljkovic says: If too many droplets form, they can “flood” the surface, reducing its heat-transfer ability. “We are working on delaying this surface flooding and creating more robust solutions that can work well [under] all operating conditions,” he says.
Yi Cui, an associate professor of materials science and engineering at Stanford University, calls the concept behind this work “an excellent idea,” and adds, “The studies here can lead to better atmospheric water-harvesting and dehumidification, and efficient heat transfer.” Cui adds that the fact that this team was able to make direct measurements of the actual heat-transfer enhancement from these treated surfaces is “interesting and important.”
The research team also included postdocs Ryan Enright and Youngsuk Nam and undergraduates Ken Lopez, Nicholas Dou and Jean Sack, all of MIT’s mechanical engineering department. The work was supported by MIT’s Solid-State Solar Thermal Energy Conversion Center, the U.S. Department of Energy, the National Science Foundation and the Irish Research Council for Science, Engineering and Technology.
Source: MIT
Jan 4, 2013
Many industrial plants depend on water vapor condensing on metal plates: In power plants, the resulting water is then returned to a boiler to be vaporized again; in desalination plants, it yields a supply of clean water. The efficiency of such plants depends crucially on how easily droplets of water can form on these metal plates, or condensers, and how easily they fall away, leaving room for more droplets to form.
The key to improving the efficiency of such plants is to increase the condensers’ heat-transfer coefficient — a measure of how readily heat can be transferred away from those surfaces, explains Nenad Miljkovic, a doctoral student in mechanical engineering at MIT. As part of his thesis research, he and colleagues have done just that: designing, making and testing a coated surface with nanostructured patterns that greatly increase the heat-transfer coefficient.
The results of that work have been published in the journal Nano Letters, in a paper co-authored by Miljkovic, mechanical engineering associate professor Evelyn Wang, and five other researchers from the Device Research Lab (DRL) in MIT’s mechanical engineering department.
On a typical, flat-plate condenser, water vapor condenses to form a liquid film on the surface, drastically reducing the condenser’s ability to collect more water until gravity drains the film. “It acts as a barrier to heat transfer,” Miljkovic says. He and other researchers have focused on ways of encouraging water to bead up into droplets that then fall away from the surface, allowing more rapid water removal.
“The way to remove the thermal barrier is to remove [the droplets] as quickly as possible,” he says. Many researchers have studied ways of doing this by creating hydrophobic surfaces, either through chemical treatment or through surface patterning. But Miljkovic and his colleagues have now taken this a step further by making scalable surfaces with nanoscale features that barely touch the droplets.
The result: Droplets don’t just fall from the surface, but actually jump away from it, increasing the efficiency of the process. The energy released as tiny droplets merge to form larger ones is enough to propel the droplets upward from the surface, meaning the removal of droplets doesn’t depend solely on gravity.
 |
| Jumping-droplet superhydrophobic condensation shown on a nanostructured CuO tube. Image courtesy of the researchers |
Other researchers have worked on nanopatterned surfaces to induce such jumping, but these have tended to be complex and expensive to manufacture, usually requiring a clean-room environment. Those approaches also require flat surfaces, not the tubing or other shapes often used in condensers. Finally, prior research has not tested the enhanced heat transfer predicted for these types of surfaces.
In a paper published early in 2012, the MIT researchers showed that droplet shape is important to enhanced heat transfer. “Now, we’ve gone a step further,” Miljkovic says, “developing a surface that favors these kinds of droplets, while being highly scalable and easy to manufacture. Furthermore, we’ve actually been able to experimentally measure the heat-transfer enhancement.”
The patterning is done, Miljkovic says, using a simple wet-oxidation process right on the surface that can be applied to the copper tubes and plates commonly used in commercial power plants.
The nanostructured pattern itself is made of copper oxide and actually forms on top of the copper tubing. The process produces a surface that resembles a bed of tiny, pointed leaves sticking up from the surface; these nanoscale points minimize contact between the droplets and the surface, making release easier.
Not only can the nanostructured patterns be made and applied under room-temperature conditions, but the growth process naturally stops itself. “It’s a self-limiting reaction,” Miljkovic says, “whether you put it in [the treatment solution] for two minutes or two hours.”
After the leaflike pattern is created, a hydrophobic coating is applied when a vapor solution bonds itself to the patterned surface without significantly altering its shape. The team’s experiments showed that the efficiency of heat transfer using these treated surfaces could be increased by 30 percent, compared to today’s best hydrophobic condensing surfaces.
That means, Miljkovic says, that the process lends itself to retrofitting thousands of power plants already in operation around the world. The technology could also be useful for other processes where heat transfer is important, such as in dehumidifiers and for heating and cooling systems for buildings, the authors say.
Challenges for this approach remain, Miljkovic says: If too many droplets form, they can “flood” the surface, reducing its heat-transfer ability. “We are working on delaying this surface flooding and creating more robust solutions that can work well [under] all operating conditions,” he says.
Yi Cui, an associate professor of materials science and engineering at Stanford University, calls the concept behind this work “an excellent idea,” and adds, “The studies here can lead to better atmospheric water-harvesting and dehumidification, and efficient heat transfer.” Cui adds that the fact that this team was able to make direct measurements of the actual heat-transfer enhancement from these treated surfaces is “interesting and important.”
The research team also included postdocs Ryan Enright and Youngsuk Nam and undergraduates Ken Lopez, Nicholas Dou and Jean Sack, all of MIT’s mechanical engineering department. The work was supported by MIT’s Solid-State Solar Thermal Energy Conversion Center, the U.S. Department of Energy, the National Science Foundation and the Irish Research Council for Science, Engineering and Technology.
Source: MIT
New 2D material for next generation high-speed electronics
Engineerblogger
Jan 4, 2013
Scientists at CSIRO and RMIT University have produced a new two-dimensional material that could revolutionise the electronics market, making “nano” more than just a marketing term.
The material – made up of layers of crystal known as molybdenum oxides – has unique properties that encourage the free flow of electrons at ultra-high speeds.
In a paper published in the January issue of materials science journal Advanced Materials, the researchers explain how they adapted a revolutionary material known as graphene to create a new conductive nano-material.
Graphene was created in 2004 by scientists in the UK and won its inventors a Nobel Prize in 2010. While graphene supports high speed electrons, its physical properties prevent it from being used for high-speed electronics.
The CSIRO's Dr Serge Zhuiykov said the new nano-material was made up of layered sheets – similar to graphite layers that make up a pencil's core.
"Within these layers, electrons are able to zip through at high speeds with minimal scattering," Dr Zhuiykov said.
"The importance of our breakthrough is how quickly and fluently electrons – which conduct electricity – are able to flow through the new material."
RMIT's Professor Kourosh Kalantar-zadeh said the researchers were able to remove "road blocks" that could obstruct the electrons, an essential step for the development of high-speed electronics.
"Instead of scattering when they hit road blocks, as they would in conventional materials, they can simply pass through this new material and get through the structure faster," Professor Kalantar-zadeh said.
"Quite simply, if electrons can pass through a structure quicker, we can build devices that are smaller and transfer data at much higher speeds.
"While more work needs to be done before we can develop actual gadgets using this new 2D nano-material, this breakthrough lays the foundation for a new electronics revolution and we look forward to exploring its potential."
In the paper titled 'Enhanced Charge Carrier Mobility in Two-Dimensional High Dielectric Molybdenum Oxide,' the researchers describe how they used a process known as "exfoliation" to create layers of the material ~11nm thick.
The material was manipulated to convert it into a semiconductor and nanoscale transistors were then created using molybdenum oxide.
The result was electron mobility values of >1,100 cm2/Vs – exceeding the current industry standard for low dimensional silicon.
The work, with RMIT doctoral researcher Sivacarendran Balendhran as the lead author, was supported by the CSIRO Sensors and Sensor Networks Transformational Capability Platform and the CSIRO Materials Science and Engineering Division.
It was also a result of collaboration between researchers from Monash University, University of California – Los Angeles (UCLA), CSIRO, Massachusetts Institute of Technology (MIT) and RMIT.
Source: CSIRO
Jan 4, 2013
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| Artist impression of high carrier mobility through layered molybdenum oxide crystal lattice. Credit: Dr Daniel J White, ScienceFX |
Scientists at CSIRO and RMIT University have produced a new two-dimensional material that could revolutionise the electronics market, making “nano” more than just a marketing term.
The material – made up of layers of crystal known as molybdenum oxides – has unique properties that encourage the free flow of electrons at ultra-high speeds.
In a paper published in the January issue of materials science journal Advanced Materials, the researchers explain how they adapted a revolutionary material known as graphene to create a new conductive nano-material.
Graphene was created in 2004 by scientists in the UK and won its inventors a Nobel Prize in 2010. While graphene supports high speed electrons, its physical properties prevent it from being used for high-speed electronics.
The CSIRO's Dr Serge Zhuiykov said the new nano-material was made up of layered sheets – similar to graphite layers that make up a pencil's core.
"Within these layers, electrons are able to zip through at high speeds with minimal scattering," Dr Zhuiykov said.
"The importance of our breakthrough is how quickly and fluently electrons – which conduct electricity – are able to flow through the new material."
RMIT's Professor Kourosh Kalantar-zadeh said the researchers were able to remove "road blocks" that could obstruct the electrons, an essential step for the development of high-speed electronics.
"Instead of scattering when they hit road blocks, as they would in conventional materials, they can simply pass through this new material and get through the structure faster," Professor Kalantar-zadeh said.
"Quite simply, if electrons can pass through a structure quicker, we can build devices that are smaller and transfer data at much higher speeds.
"While more work needs to be done before we can develop actual gadgets using this new 2D nano-material, this breakthrough lays the foundation for a new electronics revolution and we look forward to exploring its potential."
In the paper titled 'Enhanced Charge Carrier Mobility in Two-Dimensional High Dielectric Molybdenum Oxide,' the researchers describe how they used a process known as "exfoliation" to create layers of the material ~11nm thick.
The material was manipulated to convert it into a semiconductor and nanoscale transistors were then created using molybdenum oxide.
The result was electron mobility values of >1,100 cm2/Vs – exceeding the current industry standard for low dimensional silicon.
The work, with RMIT doctoral researcher Sivacarendran Balendhran as the lead author, was supported by the CSIRO Sensors and Sensor Networks Transformational Capability Platform and the CSIRO Materials Science and Engineering Division.
It was also a result of collaboration between researchers from Monash University, University of California – Los Angeles (UCLA), CSIRO, Massachusetts Institute of Technology (MIT) and RMIT.
Source: CSIRO
Doris Kim Sung: Metal that breathes
Engineerblogger
Jan 4, 2013
Modern buildings with floor-to-ceiling windows give spectacular views, but they require a lot of energy to cool. Doris Kim Sung works with thermo-bimetals, smart materials that act more like human skin, dynamically and responsively, and can shade a room from sun and self-ventilate.
Doris Kim Sung is a biology student turned architect interested in thermo-bimetals, smart materials that respond dynamically to temperature change.
Source: Ted
Additional Information:
Jan 4, 2013
Modern buildings with floor-to-ceiling windows give spectacular views, but they require a lot of energy to cool. Doris Kim Sung works with thermo-bimetals, smart materials that act more like human skin, dynamically and responsively, and can shade a room from sun and self-ventilate.
Doris Kim Sung is a biology student turned architect interested in thermo-bimetals, smart materials that respond dynamically to temperature change.
Source: Ted
Additional Information:
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