Friday 28 February 2014

Rare natural phenomena - Grid Waves

Cross seas occur when two sets of waves traveling from different directions overlap and create short-crested waves.

Nature, the best designer


Arizona Superstition Mountain


Before and after of Kiev's independence square in Ukraine


A Stockbroker walks into the dentist and asks for an amount for getting a tooth pulled out.

‘Well,’ said the dentist, ‘That depends on the level of service. If you want to go private we can give you the very best and latest in dental treatment. We get an anesthetist in from the local hospital, and I get two very skilled, and pretty, dental nurses to help out. Guaranteed no pain, no blood.’




‘Sounds good,’ said the man, ‘how much?’

‘£200 per tooth.’

‘That’s extortionate!’

‘Well,’ said the dentist, ‘We can give you standard NHS treatment. I do the anesthetic myself – no nurses. You get a little bit of pain and a little bit of blood, but it’ll only cost you £20.’

‘No, that’s still too dear. Can you not do it a bit cheaper?’

‘Tell you what,’ said the dentist, getting angry, ‘I could get a pair of pliers from B&Q and do a homer for you. No anesthetic. Guaranteed very painful – lots of blood. Your mouth will hurt for three months and you’ll struggle to talk for at least two. I’d do it for £5 and take pleasure in it.’

Engineer


Thursday 27 February 2014

Hybrid Toyota Roadster Shocks Audience

Everyone needs a hobby, but what if you’re a Toyota engineer and building technologically advanced prototypes is your hobby? Don’t you get enough of that at work? Apparently not, since that was the motivation behind the plug-in sportscar you see here. Built on an old MR2 platform using from Toyota’s corporate Prius/Corolla parts bins by company engineers with a lot of free time on their hands, the Toyota TE-S800 is a sweet-looking plug-in hybrid roadster that weighs less than 2000 lbs. and rockets to 60 MPH in just 5.8 seconds (!).




Motive power is provided by Toyota’s 1.5 liter Otto-cycle 1NZ-FE engine , sold in the US under the hood of the latest Prius. The car features a free-flowing sport exhaust that allows the engine to kick out more than 115 hp at 6400 rpm. That engine is boosted by the plug-in Prius’ 102 hp electric motor coupled to a Toyota E-CVT transmission.

The TE-S800 was quietly unveiled at the Tokyo Auto Salon, but didn’t get much press since it wasn’t an “official” project. All the same, this hybrid roadster is based on a chassis that met US crash standards the last time it was imported, and is powered by a drivetrain that is definitely clean enough to meet US emissions standards. What do you guys think? Is this the kind of mid-engined go-fast hybrid Toyota should build, or would you be more excited about a KERS-equipped FR-S or the more luxurious Lexus RC300h ? Let us know what direction you’d like to see Toyota take in the comments section.

BYD Makes Electric Buses That Can Go 30 Hours On Single Charge

BYD’s electric buses can run for an impressive 30 or so hours straight in between charges, based on the results of a pilot test performed in New York City last year during the months of August–October. Charging to full capacity took, roughly, 3–4 hours, and was completed at night.





According to SAE International (the Society of Automotive Engineers), one of BYD’s buses was used on a number of different routes in Manhattan during that span of time, and ran for a total of 1,481 miles. The pilot test proved that the electric bus could indeed approach the 155-mile-range advertised by BYD.

Here’s some more info from SAE:

After two months, the electric bus’s average battery duration was 0.3 h per % SOC, or 30 h of operation per full charge. An advantage of electric buses, compared to diesel bus technology, is that they do not idle when in heavy or stopped traffic, thus conserving “fuel” and reducing greenhouse gas emissions. Another advantage is that because BYD buses do not have an internal-combustion engine or transmission, along with other conventional components, maintenance costs (and labor) can be reduced “significantly,” according to the company. Regenerative braking also reduces normal brake-pad wear and maintenance.

BYD and MTA claim that the expected operating-cost-per-mile of an electric bus is about $0.20 to $0.30, compared to $1.30 per mile for an equivalent diesel- or natural-gas-powered bus in New York.

In related news, Daimler-BYD’s first Denza electric car is nearing its release date — the model is expected to be released in China sometime towards the middle of the year. Recent reports have revealed that the EV will be DV quick-charge compatible.

US researchers make a 3D printer to build houses




The huge 3D printer, built by researchers in the US, is still being tested, but could make houses cheaper to build and easier to repair. The printer operates on two rails and glides back and forth spraying concrete from its nozzle - just like a traditional printer would lay down ink. Human workers will then complete the rest of the building, such as hanging doors and installing windows.

Real


Tuesday 25 February 2014

Geometric Dimensioning and Tolerance for Vestas Wind Turbines

Vestas Wind Systems’ goal is to provide the cheapest, most reliable wind turbines in the world. Geometric dimensioning and tolerancing (GD&T) is an important step to ensure these robust designs.
To perform their GD&T, Vestas has chosen Sigmetrix’ CETOL 6 Sigma and GD&T Advisor software. Sigmetrix produces tolerance analysis software which helps engineers bring their designs to the manufacturing stage of development.




Third party wind turbine expert Dr. David Lubitz (University of Guelph) explains that, "wind turbines are complex, sophisticated machines, and many of the challenges in design and manufacture are shared with things like airliners and other aerospace systems. Minimum weight and high reliability are both required, at the lowest cost possible, so design and manufacturing must be very precise. Accurate tolerancing is an essential part of that process."


Essentially, the software ensures that the design for drawing assemblies is within acceptable variances when produced as a physical product. To do this, the software calculates and optimizes the design’s surface sensitivities needed for quality dimensioning and assemblies.

“CETOL 6 Sigma is the dominant solution for variation analysis in many industries,” said Sigmetrix President Chris Wilkes. “We’re excited to be incorporated into Vestas’ quality enhancement program and look forward to our involvement in the planning and manufacturing of their green energy solution products.”
Vestas provides wind energy to 73 countries globally. They have installed over 60GW worth of turbines in total; 62% more than their nearest competitor.

According to Vestas VP Carl Erik Skjølstrup, “As a leader in wind turbine manufacturing, robustness and quality is of the outmost [sic] importance to us and vital to the industry as the demand for more cost effective, reliable, green sources of energy continues to increase … CETOL 6 Sigma and GD&T Advisor will play an integral part in improving our design robustness and the quality of wind energy solutions as well as optimizing our design and manufacturing goals.”

This Isn't Your Father's Power Suit

Imagine a suit that can charge your phone. No, it won’t have solar panels built into it. Instead, it will be made of 3D fibers with piezoelectric properties, thanks to research being done by Dr. Navneet Soin and his colleagues at the University of Bolton in the UK. Their latest paper in the journal Energy and Environmental Science describes a wearable energy harvesting technology made of piezoelectric fibers. Unlike other micro-sized piezoelectric devices, which are brittle, uncomfortable, and costly, Dr. Soin’s “3D spacer technology” makes fibers that are resilient, lightweight, and inexpensive.



Instead of being added to the material, the energy harvesters are woven directly into the fabric. According to Soin and his colleagues, the knitted piezoelectric generator consists of polyvinylidene fluoride (PVDF) monofilament spacers (the vertical objects in the above image) sandwiched between electrodes made of silver-coated polyamide multifilament yarn layers. The fabric is produced using warp knitting or welt knitting, both of which are standard textile industry techniques.

How powerful are they? With pressures of only 0.10 MPa (14.5 PSI) the material generates up to 5 microwatts per square centimeter. That’s enough to power small wearable sensors and low-power personal electronic devices.

Further work will optimize the energy production and ensure durability. The research team believes that this technology could be commercially available within five years. This could give new meaning to the term “power suit.”

 

Monday 24 February 2014

Terrafugia, the Flying Car - A Moonshot Project

Carl and Ann Mracek Dietrich believe that everyone should have the opportunity to own and drive a flying car. Their company, Terrafugia, is gearing up to produce street legal airplanes for consumers.

This video shows some press for Terrafugia and one of the first media showcases for the Terrafugia Transition at the Osh Kosh Experimental Aircraft Association Fly-In Convention in 2013. Several other videos on the company’s website and YouTube site also showcase the Transition and the even more experimental TF-X. 



The two seater transition is built from a carbon fiber body and spec’ed at a cruising speed of 100 miles per hour and a range of 410 miles on a single tank of gas. The tank is said to have 23 useful gallons and as a land vehicle a whopping 35 miles per gallon is specified on the ground.

On the road the car is rear wheel drive, fits in  your garage when folded, and has cargo space for carryon bags. A 100 hp Rotax 912iS engine, automatic transmission and touchscreen driver interface are also included. Testing is planned to meet the ASTM / FAA standards for Light Sport Aircraft and FMVSS standards for automobiles.

The transition of the Transition from car to plane takes about one minute. One of the most striking things to me in the video was the way that the operator stowed the rearview mirrors inside the nose as the wings spread out – that was the extent of his work to turn the car into a plane. He then did a check of the wings and flaps to make sure everything was in working order and drove off to the runway.



Currently the launch date is set for 2016, and potential customers can reserve a Transition for $10,000 as a deposit on the expected $279,000 final price tag. The company has raised more than $11,000,000 in funding through their Wefunder site, and has amassed $30,000,000 in preorders. The ten year vision for the company is “Drive out of your garage. Takeoff vertically. Fly at over 200 mph. Get there on auto-pilot.”
There is a feeling of cautious optimism among tech bloggers and the experimental aircraft community. Almost every engineer should want to see the flying car be produced and become commonplace in the next fifty years. The Dietrichs have been working on this project since the turn of the century, and Carl won the Lemelson-MIT Student Prize for Innovation in 2006. Will it work? I sure hope so.

New Air Filter For Cars Reduces Ultrafine-Particles Exposure By 93%


A new type of high-efficiency cabin air filter (HECA) has been developed that can reduce ultrafine particles (UFPs) exposure by as much as 93%, while also keeping carbon dioxide levels low—a notable development for those that drive a lot, especially in highly polluted regions/cities.
 


For a bit of background, most modern cars feature cabin air filters, but these typically only block 40-60% of the UFPs in the air when in “outdoor air mode”.

A filter capable of blocking up to 93% of UFPs is a substantial improvement over existing technologies. The ACS press release provides more:

These particles are 100 nanometers or less in diameter; about a thousand of them could fit across the width of a human hair. Studies suggest that UFPs, which are found in automotive exhaust, may be linked with health problems. Switching the venting system into “recirculation mode” reduces UFPs by 90 percent, but because the interior is closed off from the outside, exhaled carbon dioxide can potentially build up to levels that could impair decision-making. To address this challenge, researchers Yifang Zhu and Eon Lee decided to develop a method that would simultaneously reduce UFPs inside cars, while also allowing carbon dioxide to escape. They developed HECA filters that could reduce UFP levels by an average of 93 percent in 12 commercially available vehicles while driving in outdoor air mode. Compared with the original manufacturer-installed filters, the new one is made of synthetic fibers of much smaller diameters. Carbon dioxide remained at a “reasonable” level, they say.

It’s currently unclear when these new filters will be commercially available. The new research was just published in the ACS journal Environmental Science & Technology.

Source: Clean Technica

Let's learn more about Cabin Air Filters from our new expert Mr. James Hamilton.

• What is Cabin Air Filter:
The cabin air filter collects dust, pollen, and other debris before it can enter the passenger compartment through the climate control (HVAC) system.

• Why Should It Be Serviced?
A dirty cabin air filter may affect heater and AC performance, so it's important to have it serviced. If you don't, you may experience one or more of these symptoms:
- Poor air flow from HVAC system
- Odors from HVAC system.

• When Should It Be Serviced?
We recommend replacing the cabin air filter every 12,000 to 15,000 miles.

Saturday 22 February 2014

Nanoscale pillars could radically improve conversion of heat to electricity

University of Colorado Boulder scientists have found a creative way to radically improve thermoelectric materials, a finding that could one day lead to the development of improved solar panels, more energy-efficient cooling equipment, and even the creation of new devices that could turn the vast amounts of heat wasted at power plants into more electricity.



The technique -- building an array of tiny pillars on top of a sheet of thermoelectric material -- represents an entirely new way of attacking a century-old problem, said Mahmoud Hussein, an assistant professor of aerospace engineering sciences who pioneered the discovery.

The thermoelectric effect, first discovered in the 1800s, refers to the ability to generate an electric current from a temperature difference between one side of a material and the other. Conversely, applying an electric voltage to a thermoelectric material can cause one side of the material to heat up while the other stays cool, or, alternatively, one side to cool down while the other stays hot.

Devices that incorporate thermoelectric materials have been used in both ways: to create electricity from a heat source, such as the sun, for example, or to cool precision instruments by consuming electricity. However, the widespread use of thermoelectric materials has been hindered by a fundamental problem that has kept scientists busy for decades. Materials that allow electricity to flow through them also allow heat to flow through them. This means that at the same time a temperature difference creates an electric potential, the temperature difference itself begins to dissipate, weakening the current it created.

Until the 1990s, scientists addressed this problem by looking for materials with intrinsic properties that allowed electricity to flow more easily than heat. "Until 20 years ago, people were looking at the chemistry of the materials," Hussein said. "And then nanotechnology came into the picture and allowed researchers to engineer the materials for the properties they wanted."

Using nanotechnology, material physicists began creating barriers in thermoelectric materials -- such as holes or particles -- that impeded the flow of heat more than the flow of electricity. But even under the best scenario, the flow of electrons -- which carry electric energy -- also was slowed.

In a new study published in the journal Physical Review Letters , Hussein and doctoral student Bruce Davis demonstrate that nanotechnology could be used in an entirely different way to slow the heat transfer without affecting the motion of electrons. The new concept involves building an array of nanoscale pillars on top of a sheet of a thermoelectric material, such as silicon, to form what the authors call a "nanophononic metamaterial." Heat is carried through the material as a series of vibrations, known as phonons. The atoms making up the miniature pillars also vibrate at a variety of frequencies. Davis and Hussein used a computer model to show that the vibrations of the pillars would interact with the vibrations of the phonons, slowing down the flow of heat. The pillar vibrations are not expected to affect the electric current.

The team estimates that their nanoscale pillars could reduce the heat flow through a material by half, but the reduction could be significantly stronger because the calculations were made very conservatively, Hussein said. "If we can improve thermoelectric energy conversion significantly, there will be all kinds of important practical applications," Hussein said. These include recapturing the waste heat emitted by different types of equipment -- from laptops to cars to power plants -- and turning that heat into electricity. Better thermoelectrics also could vastly improve the efficiency of solar panels and refrigeration devices.

Beauty in Pro-E


The World’s Largest Solar Plant is Frying Birds

The world’s largest solar power plant, the Ivanpah Solar Electric Generating System, officially opened for business a few days ago, but not all environmentalists are happy about it. The plant consists of 350,000 mirrors spread across 5 square miles, and it works by concentrating sunlight to boil water in a series of enormous towers hooked up to steam generators. That incredible amount of heat does more than just generate power, however; it also fries any birds that happen to fly over the plant.



This has actually been a known side effect of this type of solar plant from the start, and it’s a concern that may keep similar projects from being approved in the US. The air above the plant can reach temperatures up to 1,000 degrees Fahrenheit (537 Celsius), and the reflective surface of the mirrors resembles a lake, which biologists say could end up luring birds to their deaths.

The way the plant scorches birds is horrifying, but the California Energy Commission believes the loss of wildlife — about eleven birds a month — is a price worth paying for 140,000 sustainably-powered homes. While any loss of life is upsetting, the fact of the matter is it’s a drop in the bucket compared to the number of birds killed by other forms of human infrastructure: an estimated minimum of 300 million birds a year are killed simply by colliding into buildings. Even domesticated cats kill far greater numbers of birds each year. And other forms of clean energy can be just as problematic as the tower solar plants, with wind turbines killing at least 10,000 birds a year (some of them bald eagles ).

No power generating system that harms wildlife is ideal, but this type of solar plant is still vastly less harmful to birds than the alternatives. After all, coal-fired plants harm more than a handful of birds each month — they release greenhouse gasses and toxic pollutants, warming the planet and making people and animals near the plants ill. Unlike a nuclear power plant, the catastrophic failure of a solar plant won’t leave the surrounding area tainted with radioactivity for decades or centuries to come. It’s likely the Ivanpah plant will remain controversial due to the bird death toll, but in the grand scheme of things, it’s far less damaging to the environment than the other energy sources we’re already using.

Thursday 20 February 2014

Tatoostyle by Jackie Rabbit


This is the microscopic image of the human tongue.


Meanwhile Somewhere in


Schienenzeppelin - A German high speed train from the 1930s. Top speed was 210 km-h (130mph).


He must be an engineer.


Terrifying torture devices from across time! I can't believe they used these inhumane methods to extract info - see all pictures


Because who needs physics


Kings Canyon, Australia


Do you know


Benefits of Banana


shooo cute


Monday 17 February 2014

Mahindra Rolls Out Halo Electric Sports Car Concept At 2014 Delhi Auto Expo

Indian automaker Mahindra, mostly known for its SUVs and pickup trucks, has rolled out a sleek electric sports car concept at the 2014 Delhi Auto Expo this week. The new concept is called the Halo, and it’s destined to be one of the hottest products from Mahindra’s electric car division, Mahindra Reva.



Helping with the design of the Halo concept were leading design firms Pininfarina and Bertone, and evidence of their talents can clearly be seen in the styling. The interior layout in particular is similar to what you find in many high-end Italian sports cars. Italy’s sports car manufacturers needn’t worry just yet, however. The Halo concept’s electric motor develops just 104 kilowatts (140 horsepower), which is enough to accelerate the small two-seater from 0-62 mph in about 9.0 seconds and see it reach a top speed of 100 mph. As for the driving range, Mahindra says the largest battery pack designed for the car offers a range of about 125 miles.

If all goes to plan, Mahindra hopes to have the Halo in production by next year. Note, the company is serious about investing in electric car technology. The Mahindra Reva division already has a number of zero-emission vehicles on sale and later this year it will start competing in the Formula E Championship .

Mechanical Beauty


Finally, Subcompact EV Hatchback For Drivers In Wheelchairs

More than three million Americans can celebrate when they hear this story. Made in the USA but in demand worldwide, the Kenguru—a driver-only electric vehicle with no seats—promises mobility-challenged people unprecedented access to the everyday world the rest of us take for granted.



Imagine you can’t jump into a car quickly when it is raining, are unable to ride a bike, and most public transportation is not accessible to you. Transportation is a huge obstacle for people who use wheelchairs. It is often time-consuming, physically difficult, expensive, or just unavailable. This results in a disconnect from the community, an inability to work, and a lower quality of life…. Can you imagine having to depend on someone every time you wanted to leave your house?

The design of the Kenguru (Hungarian for “kangaroo” and pronounced the same) allows mobility-limited people to drive a car solely from their wheelchairs. The alternative, outfitting a van for wheelchair accessibility, costs over three times as much as the Kenguru price tag of $25,000—and that’s without zero-emission EV or vocational rehab incentives. Short neighborhood trips to places like a convenience store, park, or nearby mall are the Kenguru’s specialty. It’s over a foot shorter than the smart fortwo . The Kenguru allows drivers to get into the car and drive without leaving the wheelchair. To enter the vehicle, the driver pushes a button and remotely opens the back (only) door. (No room for passengers.) A ramp comes down. Wheel the chair in and drive the car. Lock it when you stop. The current model has motorcycle bars for handling and is designed for manual wheelchair-users like people with MS, who have upper body strength. A joystick-steering model is in development for people who use electric wheelchairs.

Patented airflow system decreases pollutants from large piston engines



 

A patent was recently issued to Kansas State University for a system that controls the airflow to pistons in reciprocating internal combustion engines -- engines powered by pistons. The system enables large-bore, multi-cylinder engines used in trains, pipelines, backup diesel generators and other fields to run efficiently while producing lower levels of harmful emissions than they do currently.

The patent, "Active Air Control," was issued to the Kansas State University Research Foundation, a nonprofit corporation responsible for managing technology transfer activities at the university. The patent is for research by former faculty member Kirby Chapman and doctoral graduate Diana Grauer.

The Kansas State University-developed system uses an airflow sensor to measure and control the airflow rate into each piston in real time. Algorithms adjust the airflow accordingly and equalize the rate in multiple cylinders at the same time. This reduces the levels of nitrogen oxides produced during combustion in the engine.

The air control system offers a low-cost method to control and lower the production of nitrogen oxides and helps legacy engines meet compliance with EPA 2011 regulations. The system also was designed to fit various engine systems.

Artist Creates a Breathing Bike to Combat Beijing Pollution




How does an artist cope with China's massive pollution challenge? Beijing-based artist Matt Hope used his mechanical engineering background to create this amazing breathing machine using a Walmart bicycle cobbled together with various found components, such as a wind generator, an Ikea trash can and a Chinese fighter pilot mask. The bike generates clean air through an electromechanical filtration system. Air gets pulled into the bike through an Ikea trashcan, and the dust particles get positively charged and stick to a metal trumpet. The cleaned air gets propelled through a tube to the gas mask, fit for breathing.

Types of Gears

Researchers 'design for failure' with model material

When deciding what materials to use in building something, determining how those materials respond to stress and strain is often the first task. A material's macroscopic, or bulk, properties in this area—whether it can spring back into shape, for example—is generally the product of what is happening on a microscopic scale. When stress causes a material's constituent molecules to rearrange in a way such that they can't go back to their original positions, it is known as "plastic deformation."



Researchers at the University of Pennsylvania have devised a method to study stress at the macro and micro scales at the same time, using a model system in which microscopic particles stand in for molecules. This method has allowed the researchers to demonstrate an unusual hybrid behavior in their model material: a reversible rearrangement of its particles that nevertheless has the characteristics of plastic deformation on the macroscale. That kind of plastic deformation is more akin to what happens with ketchup or toothpaste, a liquid-like flowing instead of a brittle fracturing of the material's particles.

Their study could pave the way for designing this potentially useful trait into new materials. Plastic deformation dissipates energy rather than transferring it, so a material that could repeatedly deform in this way could be used to dampen vibrations or protect against impacts.

The study was conducted by postdoctoral researcher Nathan Keim and professor Paulo Arratia, both of the Department of Materials Science and Engineering in Penn's School of Engineering and Applied Science. It was published in Physical Review Letters . "If you're driving your car and you hit a lamppost, your car would be totally deformed," Arratia said. "That's plastic deformation because it's irreversible. When you put your car into reverse and back up away from the lamppost, it's not as if the car just springs back into shape. And even if you take it to the body shop and hammer it out to look like new, it's never going to be the same again on the atomic level."

"On the other end of the spectrum," Keim said, "there's elastic deformation. Those deformations are usually reversible rearrangements. If you take a piece of steel and deform it just a little bit, like sitting on the hood of your car rather than running it into a lamppost, it will come back exactly as it started, even on the microstructural level.

"What we were able to show with this model is that you can have something that's between the two ends of this spectrum, a hybrid regime that is plastic but also reversible."

Simultaneously investigating both the macroscopic and microscopic behavior of a material under stress time is a challenge: bulk materials are generally opaque, so seeing what is happening inside of them while they maintain their bulk properties is impossible. To provide a window to this inner world, the researchers built a model material that sacrifices complexity for access. "The complexity we sacrificed is the third dimension," Keim said. "We have made an effectively 2-D material in the lab that consists of microscopic particles that sit on an oil-water interface. These particles have a little electric charge that keeps them constantly pushing away from each other, which means you can think of them as drops of liquid in an emulsion or even as atoms."

The researchers used this model material to study a behavior known as the "yielding transition," which is how disordered solids begin to flow. Just as toothpaste doesn't immediately flow out of the tube and ketchup doesn't pour out of the bottle once the cap is removed, the particles of a disordered solid are jammed against one another and don't easily rearrange themselves unless outside energy is added. In the case of ketchup, this outside energy often takes the form of tapping the side of the bottle.

In the case of this model material, the researchers added this energy by way of a needle that also sat at the material's oil-water interface, in the plane with the rest of the particles. Using an electromagnetic field, they could swing the needle back and forth against the particles and measure how much resistance they provided.

In experimenting with this model material, the researchers were surprised by what they described as a "learned behavior." They found that by repeatedly moving the needle back and forth, irreversibly deforming the material many times, the particles eventually rearranged themselves in such a way that they went back to their original state after each cycle of deformation. "The material can reorganize itself so that the link between plasticity and irreversibility is broken," Arratia said. "The material flows slightly, and yet, at the end of each cycle, it is exactly unchanged."

Critically, this reversible rearrangement of particles is not like what happens in elastic deformations. "After the material is deformed," Keim said, "it doesn't just bounce back to its original state. Rather than just pushing back elastically, like a spring would, it gives a little bit and dissipates energy, more like a viscous fluid than a solid." Having a mix of plastic and elastic properties is potentially useful.

"You might want this in materials where the alternative to flowing is shattering," Keim said. "You'd rather that it deform a little bit before breaking, and you'd also want things not to be severely altered or damaged by being deformed again and again. This kind of plastic deformation also dissipates a lot more energy; you want the body of your car to absorb the energy of an impact and dissipate it, not transfer it to you."

While this behavior has now only been observed in the researchers' model material, understanding the conditions in which it arises could lead to ways of producing it in materials that might be used outside the lab.

"We are designing for failure," Arratia said. "Elastic deformation is pretty great, but it can't last forever, eventually something has to give. And when it gives, this would be a pretty great way to do it. You'd like that transition to be as graceful and non-destructive as possible."

IN PHOTO: A map of a portion of the material. Dots represent particle positions, and circles represent rearrangements.

Monday 10 February 2014

Fire ants inspire new process for storing and dissipating energy

U.S. Army-sponsored researchers at Georgia Institute of Technology have discovered a process for simultaneously storing and dissipating energy within structures that could lead to design rules for new types of active, reconfigurable materials for structural morphing, vibration attenuation and dynamic load mitigation.



The research was funded by the Army Research Office, an element of the U.S. Army Research Laboratory located at Research Triangle Park, N.C. ARO initiates the scientific and far reaching technological discoveries in extramural organizations, educational institutions, nonprofit organizations and private industry.

In particular, researchers examined how a species of South American fire ants collectively entangle themselves to form an active structure capable of changing state from a liquid to a solid when subject to applied loads. An ant's swarm intelligence leading to continual construction could also be applied to modular robotics research or possibly inspire new methods for actively reconfiguring interconnections in complex networks.

The team includes Jet Liu, an undergraduate at Georgia Tech; Sulisay Phonekeo, a graduate student; and their supervisor David Hu, who is an assistant professor of mechanical engineering and biology. They presented their work at two separate conferences – APS Division of Fluid Dynamics in November 2013, and at the Society of Integrative and Comparative Biology Meeting, which was held in January, 2014. Although all of the experiments were done at Georgia Tech, Hu explained that the directions of the research stem from "many useful conversations" between himself and Dr. Samuel Stanton, program manager at ARO. "This has potential to influence studies in self-healing materials," said Hu. "Such materials are the basis for almost all living things, such as skin and tissue, which repair themselves when injured. This behavior could cheapen costs and make products lasts longer." Stanton further explains the testing that led to the discovery. "In oscillatory tests, the live ants revealed a rare behavior in which energy was simultaneously stored and dissipated to the same degree. Moreover, the structure was resilient over 3 orders of magnitude in frequency and 2 orders of magnitude in strain. This robust response is not describable by existing fluid or solid mechanics theories and the phenomenon has never been seen in any other active matter such as bacteria films or liquid crystals," explained Stanton. "This could lead to principles and algorithms for synthetic materials capable of actively and continually responding to external forces without need for centralized controllers." The study has the potential to aid in the building of robots and self-healing materials.

"This understanding of ants is already at play in a new project on ant bridges," said Hu. "The team discovered that vibration stimulates ants to repair their own bridges. This repair relies upon the bridge's ability to shrink in length and increase in stiffness, becoming a stronger structure."

When asked what can be learned from this discovery and how it might help the military, Stanton said, "Aside from materials and robotics applications previously mentioned, the fundamental principles shed light on how one might dynamically alter interconnections among subsystems to direct the flow of energy and entropy within networks to achieve desired macroscopic properties."

Molecular traffic jam makes water move faster through nanochannels

New research by Northwestern University researchers finds that water molecules traveling through tiny carbon nanotube pipes do not flow continuously but rather intermittently, like stop-and-go traffic, with unexpected results. 



"Previous molecular dynamics simulations suggested that water molecules coursing through carbon nanotubes are evenly spaced and move in lockstep with one another," said Seth Lichter, professor of mechanical engineering at Northwestern's McCormick School of Engineering and Applied Science. "But our model shows that they actually move intermittently, enabling surprisingly high flow rates of 10 billion molecules per second or more."

The research is described in an Editor's Choice paper, "Solitons Transport Water through Narrow Carbon Nanotubes," published January 27 in the journal Physical Review Letters . The findings could resolve a quandary that has baffled fluid dynamics experts for years. In 2005, researchers -- working under the assumption that water molecules move through channels in a constant. stream -- made a surprising discovery: water in carbon nanotubes traveled 10,000 times faster than predicted. The phenomenon was attributed to a supposed smoothness of the carbon nanotubes' surface, but further investigation uncovered the counterintuitive role of their inherently rough interior.

Lichter and post-doctoral researcher Thomas Sisan performed new simulations with greater time resolution, revealing localized variations in the distribution of water along the nanotube. The variations occur where the water molecules do not line up perfectly with the spacing between carbon atoms -- creating regions in which the water molecules are unstable and so propagate exceedingly easily and rapidly through the nanotube. Nanochannels are found in all of our cells, where they regulate fluid flow across cell membranes. They also have promising industrial applications for desalinating water. Using the newly discovered fluid dynamics principles could enable other applications such as chemical separations, carbon nanotube-powered batteries, and the fabrication of quantum dots, nanocrystals with potential applications in electronics.

Advanced Vehicle Technology - V2V Communication

One of the biggest safety and traffic flow technologies coming is vehicle-to-vehicle (V2V) communication. The National Highway Traffic Safety Administration (NHTSA) announced that it is beginning to take steps to enable V2V technology for light vehicles. It allows vehicles to communicate information about their speed, conditions, and surroundings. The technology currently being used in testing utilizes Dedicated Short Range Communications, or DSRC. It works in the 5.9 GHZ range with bandwidth of 75 MHz and a range of about 1000 meters (.62 miles). That’s certainly far enough to warn of accidents, road hazards, slower traffic flow and even pedestrians, traffic signals and crosswalks. It’s amazing, creating a sort of living mind on the roads. The implications are huge. Coupled with technologies like adaptive cruise control, it could even help adjust speeds between cars to make traffic flow much faster on freeways and highways. And more fuel efficient. The icing on this cake is a potential 81% lower accident rate. That means less injuries, less fatalities and lower insurance rates. Airbags, seat belts and ABS are all great, but not getting into an accident in the first place is even better.



In 2012, the DOT conducted a test using 3000 connected vehicles (cars, trucks and buses). The vehicles were able to send and receive anonymous safety data between one another, and they were able to communicate warnings to drivers in cases of possible crashes. This technology will be even more useful when it rolls out in larger numbers of new vehicles. The average vehicle on the road is 11 years old, meaning that it will take a years to reach critical mass to make it truly effective. There is talk of using smartphone apps to assist in this, though they would have to be coupled to another device in the car. GM has been experimenting with transponders. Possibly in the same way you can currently add a bluetooth speaker to your car to work with your phone in cars that don’t have it built in, you could have a device that does much the same for V2V, working with your smartphone (or without). It’s doubtful that could all be built in to your smartphone, as that adds a whole new radio. Think bigger, heavier phone with more battery drain. And unnecessary for anyone who doesn’t drive.

The World’s Largest Solar Bridge Launched This January In The City of London

After two long years of waiting, the city of London is now a proud owner of the world’s largest solar bridge. The massive construction located at the Blackfriars station is equipped with 4,400 photovoltaic panels, providing half of the energy required to operate all services there.



The solar panels, together with the electric trains that run through the station, are not only going to reduce the carbon footprint of the station, but they will also serve as a symbol of what a sustainable city should look like. The project was executed by Network Rail, with partnership of Solarcentury, who was responsible for installing the panels, while trying not to interfere with commuting times during London 2012 Olympics. Thanks to careful planning, and strict organization, however, the specialists managed to complete the task in time despite heavy traffic, safety standards and restrictions.

The panels are expected to contribute to reduction in carbon emissions by 511 tonnes annually. The routes that run through the solar bridge provide a connection for the citizens from southeast England with central London, making the Blackfriars station one of the busiest locations in the city. Of course, having the bridge at such a central spot, allows people to admire it and hopefully it makes them realize how important sustainable living and green energy are. Besides raising awareness and encouraging local people and tourists to embrace a more sustainable lifestyle, the developers hope to inspire other major infrastructure developers to include renewable energy into their projects. And who knows, maybe soon most stations in the big city will be completely powered by renewables?!

Thursday 6 February 2014

New sensor system improves indoor air quality, makes building ventilation more energy efficient

A research consortium being coordinated at Saarland University is developing a novel sensor system for monitoring airborne contaminants that will provide high-quality indoor air without the energy losses typically associated with ventilation. Energy consumption levels can be halved as a result. Professor Andreas Schütze is an expert in gas sensor technology at Saarland University and is the coordinator of the European research project 'SENSIndoor'.



Researchers plan to develop a cost-effective, intelligent ventilation system that will automatically supply fresh air to rooms and indoor spaces as and when needed. The gas sensors detect air contamination due to the presence of volatile organic compounds (VOCs). Using the measurement data and information on when and how rooms are used, the system will be able to adjust the intensity and duration of ventilation. The project is being supported by the EU through a grant worth €3.4 million.

If windows are kept closed, indoor air can become a very unhealthy mix of chemicals, such as formaldehyde from furniture, solvents from carpet adhesives, chemical vapors from cleaning agents, benzene, xylene, and numerous others. This is particularly true when buildings have been well insulated and sealed to reduce energy costs. But what is good in terms of heat loss and energy efficiency, may not be so good for the health of those who live and work there. Many volatile organic compounds are carcinogens and represent a health hazard particularly to children and older people. 'If rooms are properly ventilated health hazards can be avoided. Unfortunately, our noses are usually unable to detect the presence of such contaminants, even when they are present at levels hazardous to health,' explains project coordinator Andreas Schütze. Too much ventilation also results in high levels of heat loss, which has a negative cumulative effect on energy costs and the environment.

'The sensor system that we are currently developing will maintain high-quality indoor air with the lowest possible contaminant levels while ensuring energy efficiency by means of automatic, customized ventilation,' explains Professor Schütze. 'The health hazards associated with high contaminant concentrations can therefore be avoided while at the same time reducing energy consumption in buildings by about fifty percent, which is highly significant in terms of existing carbon emission targets,' says Schütze. These highly sensitive artificial sense organs can reliably detect gases of all kinds, from toxic carbon monoxide to carcinogenic organic compounds, and can determine their concentrations quantitatively. Even the smallest quantities of trace gases do not go undetected by the sensors. The novel metal oxide semiconductor (MOS) gas sensors and so-called gas-sensitive field effect sensors, which Schütze has been developing in collaboration with partners in Sweden, Finland and Switzerland, are able to detect air contaminants such as formaldehyde, benzene or xylene at concentrations well below one in a million. However, in order to be used for the proposed application, the sensitivity of the monitoring system will need to be improved even further. The sensor system therefore collects molecules in the air over a known period of time
and then quantitatively measures the amount collected -- an approach which significantly reduces the system's detection threshold.

'If the concentration of a particular molecule is above a specified limit, fresh air is automatically introduced to modify the composition of the air and re-establish good air quality. If all of the rooms in a building are equipped with our sensors and if the sensors are connected to an intelligent ventilation control unit, the system can ventilate each room in a way that has been optimized for the specific use to which that room is put. For example, if there is a problem with contaminants in the indoor air of a school building, classroom ventilation can be adapted to fit in with teaching periods and break times,' explains Schütze. The researchers within the SENSIndoor project will therefore be studying and evaluating a variety of ventilation scenarios in schools, office buildings, homes and residential buildings. The objective is to learn more about ventilation patterns and requirements in these buildings so that the system can provide optimized ventilation under any given conditions.

Scientists create bone-like material that is lighter than water but as strong as steel

A new material has been developed which is said to be both lighter than water, and stronger than steel. The bone-like stuff was created by Jens Bauer at the Karlsruher Institute of Technology, according to Phys.org.




The reason it's so interesting, is that materials which are less dense than water - such as wood and bone - are porous, but are generally less strong than denser materials.

Theoretical studies and mathematical models have shown that it's possible to find a better balance between strength and density, with patterns on the scale of a human hair. But actually building them seemed impossible. But using Nanoscribe 3D printers, the German team was able to make a new material which is both porous and extremely strong, based on that research.

"This is the first experimental proof that such materials can exist," Jens Bauer said.

The technique is complex, involving removing areas of polymer with a computer-aided laser, then adding aluminium oxide and submitting materials to stress tests. Bauer's best result is stronger than all natural and man-made materials lighter than 1000kg/m3, and is as strong as some types of steel. Of course, making it in bulk is still a long way off - and this particular material won't be replacing traditional materials. But the more work that is done in this area, the more likely it is that one day we'll be printing the stuff our homes are made with - if not our homes themselves.

Prototype of single ion heat engine created

Scientists at Johannes Gutenberg University Mainz (JGU) and the University of Erlangen-Nuremberg are working on a heat engine that consists of just a single ion. Such a nano-heat engine could be far more efficient than, for example, a car engine or a coal fired power plant. A usual heat engine transforms heat into utilizable mechanical energy with the corresponding efficiency of an Otto engine amounting to only about 25 percent, for instance. The proposed nano-heat engine consisting of a single calcium ion would be much more efficient. The main aim of the research being conducted is to better understand how thermodynamics works on very small scales. A pilot prototype of such a single-ion heat engine is currently being constructed at Mainz University.



As the physicists explain in an article recently published in the journal Physical Review Letters , the efficiency of heat engines powered by thermal heat reservoirs is determined by the second law of thermodynamics, one of the fundamental concepts in physics. It was as far back as 1824 that Frenchman Nicolas Carnot calculated the maximum possible efficiency limit of such engines, now known as the Carnot limit.

In the case of the newly proposed nano-heat engine, the scientists have been theoretically able to exceed the classic Carnot limit by manipulating the heat baths and exploiting nonequlibrium states. Calculations and simulations made about a year ago showed for the first time that the thermo-dynamic flow in an internal combustion engine could be reproduced using individual ions. The idea was to use a calcium 40 ion, which has a diameter a million times smaller than that of a human hair, for this purpose. "Individual ions can basically act as the piston and drive shaft or, in other words, represent the entire engine," explained Johannes Roßnagel of the Quantum, Atomic, and Neutron Physics (QUANTUM) work group of the JGU Institute of Physics. Individual ions have already been captured in Paul traps and, using laser beams and electrical fields, not only cooled and heated but also compressed. "This means we are able to manipulate the pulse location distribution for optimum efficiency," added Roßnagel.

"Exceeding the Carnot limit for a standard heat engine thus does not violate the second law of thermodynamics but instead demonstrates that the use of specially prepared, non-thermal heat reservoirs also makes it possible to further improve efficiency." In their publication, the physicists calculated the general Carnot limit for this situation. As the mechanical capacity of a single ion machine is extremely low, it can probably only be used in heating or cooling nano systems.

The intention is now to actually develop the proposed single ion heat engine in initial experiments and construct a prototype in the laboratory.

In Photo: A single trapped ion in a linear Paul trap with special geometry: The heat engine is being realized by the divergent bars; the squeezing is being caused by establishing special electrical fields.

Monday 3 February 2014

Alternative Energy Breakthrough First Magma-Enhanced Geothermal System In The World Developed In Iceland

In 2009, a borehole drilled at Krafla, northeast Iceland, as part of the Icelandic Deep Drilling Project (IDDP), unexpectedly penetrated into magma (molten rock) at only 2100 meters depth, with a temperature of 900-1000 degree Celsius. The borehole, IDDP-1, was the first in a series of wells being drilled by the IDDP in Iceland in the search for high-temperature geothermal resources.



The January 2014 issue of the international journal Geothermics is dedicated to scientific and engineering results arising from that unusual occurrence. This issue is edited by Wilfred Elders , a professor emeritus of geology at the University of California, Riverside, who also co-authored three of the research papers in the special issue with Icelandic colleagues.

"Drilling into magma is a very rare occurrence anywhere in the world and this is only the second known instance, the first one, in 2007, being in Hawaii," Elders said. "The IDDP, in cooperation with Iceland's National Power Company, the operator of the Krafla geothermal power plant, decided to investigate the hole further and bear part of the substantial costs involved."

Accordingly, a steel casing, perforated in the bottom section closest to the magma, was cemented into the well. The hole was then allowed to heat slowly and eventually allowed to flow superheated steam for the next two years, until July 2012, when it was closed down in order to replace some of the surface equipment.

"In the future, the success of this drilling and research project could lead to a revolution in the energy efficiency of high-temperature geothermal areas worldwide," Elders said. He added that several important milestones were achieved in this project: despite some difficulties, the project was able to drill down into the molten magma and control it; it was possible to set steel casing in the bottom of the hole; allowing the hole to blow superheated, high-pressure steam for months at temperatures exceeding 450 degree Celsius, created a world record for geothermal heat (this well was the hottest in the world and one of the most powerful); steam from the IDDP-1 well could be fed directly into the existing power plant at Krafla; and the IDDP-1 demonstrated that a high-enthalpy geothermal system could be successfully utilized.

"Essentially, the IDDP-1 created the world's first magma-enhanced geothermal system," Elders said. "This unique engineered geothermal system is the world's first to supply heat directly from a molten magma."

Elders explained that in various parts of the world so-called enhanced or engineered geothermal systems are being created by pumping cold water into hot dry rocks at 4-5 kilometers depths. The heated water is pumped up again as hot water or steam from production wells. In recent decades, considerable effort has been invested in Europe, Australia, the United States, and Japan, with uneven, and typically poor, results.

"Although the IDDP-1 hole had to be shut in, the aim now is to repair the well or to drill a new similar hole," Elders said. "The experiment at Krafla suffered various setbacks that tried personnel and equipment throughout. However, the process itself was very instructive, and, apart from scientific articles published in Geothermics, comprehensive reports on practical lessons learned are nearing completion."

The IDDP is a collaboration of three energy companies — HS Energy Ltd., National Power Company and Reykjavik Energy — and a government agency, the National Energy Authority of Iceland. It will drill the next borehole, IDDP-2, in southwest Iceland at Reykjanes in 2014-2015. From the onset, international collaboration has been important to the project, and in particular a consortium of U.S. scientists, coordinated by Elders, has been very active, authoring several research papers in the special issue of Geothermics.
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