Super-Strong German Steel Velcro: Not for Sneakers
German-created steel fasteners can withstand loads of more than 38 tons per square meter, hook and unhook without tools
By Jeremy Hsu Posted 09.04.2009 at 2:23 pm 5 Comments
Velcro of Steel: So strong, yet still removable TUM Institute of Metal Forming and Casting (utg)
Velcro has proved plenty useful as a quick fastener on shoes and other household items, but lacks the strength to resist fiery temperatures and powerful chemicals in industrial settings. Now German scientists have taken the hook-and-loop fastener concept and developed a Superman version, called Metaklett.
The new Velcro's spring steel offers sticking strength of just over 38 tons per square meter when the pulling force is parallel to the fastener surface. Metaklett can also resist a perpendicular pulling force of almost 8 tons per square meter, and won't break a sweat regarding harsh chemicals and temperatures soaring over 1,472 degrees F.
Researchers developed several versions of their new fastener. The "Flamingo" uses wider hooks that deform slightly to glide into the perforated steel tape holes, and then revert to original form and resist back pull like an expanding river. Another model known as the "Duck's Head" has a more traditional hook and loop system where steel hooks can attach to the perforated loop tape at any angle.
The Technical University of Munich claims that the fastener "can be opened and closed again without the help of any tools," though just how that works remains unclear. But the concept impressed enough to claim a third place prize in June at the German Steel Innovation Awards.
Perhaps we can all soon look forward to steel Velcro holding together cars and buildings. But people who just want a stronger household Velcro without the ripping sound may want to check out one of PopSci's 2007 Inventions Awards winners.
New Diesel Engine Emits Cleaner Fumes
Design cuts pollution--but is it practical?
By Erika Jonietz
A new engine designed in Germany reduces the pollutants in diesel exhaust emissions to barely measurable levels. The motor relies on extremely high fuel-injection and combustion pressures to burn fuel more completely--dramatically reducing both soot and nitrogen-oxide emissions.
Diesel engines use fuel more efficiently than gasoline engines and emit less carbon dioxide, but the trade-off is that they are usually more polluting. The higher combustion temperatures required to burn diesel lead to increased nitrogen-oxide emissions. And because diesel is heavy and less volatile than gasoline, not all the fuel is burned during combustion, resulting in the formation of soot particles. The worst offenders are buses and heavy-duty trucks.
Engineers at the Technical University-Munich (TUM) designed the new engine in a three-year project called Niedrigst-Emissions-LKW-Dieselmotor (NEMo), which translates to "lowest-emission diesel truck engine." Georg Wachtmeister, chair of internal combustion engines in the university's Department of Mechanical Engineering, led the effort. Using a single-cylinder research engine, Wachtmeister's team found a balance between exhaust gas recirculation, turboboost pressure, and fuel-injector nozzle configuration that allowed them to minimize both soot and nitrogen-oxide formation.
Modern diesel engines decrease nitrogen-oxide formation by cooling down part of their exhaust and recirculating it back into the combustion chamber (together with the fresh air used to burn the fuel). In this mixture, carbon dioxide and water from the exhaust gases moderate the combustion process, keeping the temperature in check. As a result, fewer nitrogen oxides are formed--but soot production increases, since the proportion of oxygen in the air-exhaust mixture is lower and the fuel burns less completely.
The TUM researchers designed their test engine so that the turbocharger compresses the air-exhaust mixture to 10 bar--roughly 10 times the atmospheric pressure at sea level--before introducing it into the combustion chamber. In contrast, mass-production engines can compress the mixture to a maximum of about 3.5 bar. Once compressed in this way, the air-exhaust mixture in the new engine contains enough oxygen for the diesel fuel to burn more completely. The maximum air pressure inside the combustion chamber is 300 bar, double that used in most production engines.
To offset the increased soot production caused by changing the exhaust-gas recirculation rate, the NEMo team modified the fuel-injector nozzle so that it atomizes diesel fuel at a pressure of over 3,000 bar, generating a fuel mist of microscopic particles that burns very quickly and practically soot-free. The most advanced production engines today use an injection pressure of about 1,800 bar.
With the modified exhaust-gas recirculation, boost pressure, and nozzle configuration, the TUM engine almost meets European emissions standards scheduled to take effect by 2014. Those standards stipulate that a heavy-truck diesel engine can emit only five milligrams of soot particles and 80 milligrams of nitrogen oxides per kilometer. Wachtmeister says that the TUM test engine met the nitrogen-oxide limits with "no problem" and is "very close" to the soot limits.
George Anitescu, a researcher at Syracuse University, is skeptical about the project's practicality. "The research may solve, somewhat, the trade-off between particulate matter and nitrogen-oxide formation" inherent to diesel combustion, he says. But he thinks the energy needed to achieve the high pressures used will decrease the engine's efficiency. Another concern, he says, is finding materials--particularly affordable ones--that can withstand the extreme pressures.
"For the time being, turning this design into a production engine is not practical," admits Wachtmeister. The TUM Internal Combustion Engines Workshop had to specially produce 95 of the components for the test engine. However, using these special components, the team was able to successfully apply the modifications to a production truck engine.
Wachtmeister expects that it will take between five and 10 years to come up with solutions that will allow the production of engines reliable enough to run for hundreds of thousands of kilometers without failing. The turbocharger and fuel-injection system will be particularly challenging to adapt for either heavy-duty trucks or car engines.
In the meantime, he says, the design could easily be implemented today in certain industrial engines such as diesel generators, the most common type used in standby and emergency power systems. And, Wachtmeister says, automotive companies in both Germany and Japan have expressed interest in the technology.
Who'd want a Hummer, oops! Humvee...
Written by Mark
Saturday, 06 February 2010 12:35
...if you can have an M-ATV? The conclusion of a Car and Driver road test (take a look at the photo gallery):
On-road, it’ll do a maximum of 65 mph. You wouldn’t call it nimble, but there’s little steering slop and the sense that if you hit something it’s not going to matter so much anyway. Acceleration is tank-like (although 0 to 60 in 32.8 seconds is quicker than an actual tank), and it’s noisy, with a little throttle lag.
Big brake drums require significant pedal pressure, but panic stops are drama-free. The nose dives, and you can actually see the anti-lock brakes pulse the M-ATV to a halt. An ATC test driver managed 0.46 g on our improvised 200-foot-diameter skidpad (an airfield helicopter ordnance-loading pad), the M-ATV tilting obscenely and actually lifting the unloaded front wheel. But really, your mom could drive this thing.
And that’s the point. The M-ATV is for fighting as well as driving. Ease of operation means experienced MRAP drivers need only about 14 hours of instruction, complete novices just 40 hours. The M-ATV has no formal name yet, but we’re tempted for obvious reasons to call it the “B’Gosh.” In Afghanistan, the M-ATV will endure months and perhaps years of the most arduous duty, where it must bring as many soldiers home as possible. Maybe they should call it the RTB.
VEHICLE TYPE: front-engine, rear/4-wheel-drive, 4-passenger, 4-door truck
ESTIMATED PRICE AS TESTED: $1,437,000 (estimated base price: $437,000)
ENGINE TYPE: turbocharged and intercooled pushrod 18-valve diesel inline-6, iron block and head, direct fuel injection
Displacement: 442 cu in, 7242cc
Power (SAE net): 370 bhp @ 2400 rpm
Torque (SAE net): 925 lb-ft @ 1440 rpm
TRANSMISSION: 6-speed automatic with manumatic shifting
Wheelbase: 154.8 in Length: 246.8 in
Width: 98.1 in Height: 105.0 in
Curb weight: 25,000 lb
C/D TEST RESULTS:
Zero to 60 mph: 32.8 sec
Street start, 5–60 mph: 30.0 sec
Standing ¼-mile: 24.5 sec @ 54 mph
Top speed (governor limited): 65 mph
Braking, 60–0 mph: 269 ft
Roadholding, 200-ft-dia skidpad: 0.46 g
Update I: Car and Driver video:
Afstan: New US mine-resistant vehicle: The M-ATV
Not however a vehicle really relevant to the Canadian Forces since we're pulling out completely in 2011--see here and here--and already have MRAPs (mine resistant ambush protected vehicles) in theatre.
Additive manufacturing process may lead to tougher, heat-resistant components for aerospace
A new additive manufacturing process for mixing tough metals with ceramic materials and depositing, layer by layer, the mixed materials in the form of pastes could lead to stronger, heat-resistant, three-dimensional components for future space exploration, says a researcher at Missouri University of Science and Technology
Leu and his colleagues in Missouri S&T's Center for Aerospace Manufacturing Technologies (CAMT) are developing a way to create "functionally graded" material components that could be used for hypersonic aircraft or as parts of ultra-high-temperature engines and rocket boosters.
The research combines the metal and ceramic through the process of extrusion, which is similar to squeezing toothpaste through a tube but is precisely controlled. The result of squeezing the pastes of metal, ceramic and binder (the polymer and water) is a blended material that combines the toughness of the metal with the heat resistance of the ceramic. But the true value of the process, says Leu, is that it allows manufacturers to create customized parts for aircraft, spacecraft or other products.
"By controlling the extrusion forces, we can customize the percentage composition of each of the materials in the final product," says Leu, who is the Keith and Pat Bailey Missouri Distinguished Professor of Integrated Product Manufacturing.
With this process, a paste of ceramic material -- zirconium carbide, which is used to manufacture cutting tools -- is pushed through one tube, while the metal tungsten is pushed through a second. From a third tube comes a mixture of materials that is converted into zirconium carbide and tungsten after reaction sintering. From there, the functionally graded material is freeze-dried in a vacuum, the binder removed, and the final component reaction-sintered.
"In order to create high-performance combustion components or high-performance hypersonic vehicles that can sustain extreme heat and minimize thermal stresses, these types of functionally graded materials will be needed," says Leu.
Better, Stronger, Faster: New Military Vehicle Will Improve Safety and Efficiency for Marine Corps
Those who recall the old Jeep, of World War II fame, may view today's imposing Humvee as a cutting-edge vehicle. Yet the 1970s-designed Humvee has been the military's all-around workhorse almost as long as the Jeep was -- and commanders today are calling for a vehicle more suited to 21st century tasks and perils.
Georgia Tech Research Institute (GTRI) engineers are producing a technology demonstrator vehicle called the ULTRA AP (Armored Patrol). The ULTRA AP will emphasize high-output diesel power combined with revolutionary armor and a fully modern chassis.
Engineers at the Georgia Tech Research Institute (GTRI) recently took on the substantial challenge of developing revolutionary, "leap-ahead" designs for not one, but two, new Marine Corps vehicles. The GTRI researchers have been joined by an outside team that includes professional vehicle designers. The aim is to unite academic expertise with real-world, advanced engineering and production-level experience.
"What's different about this for Georgia Tech is we're partnering with very senior people from the auto industry," says Mike Dudzik, a GTRI technical fellow. "These are people who are well known for building affordable, high-performance vehicles, such as for NASCAR, with maximal use of existing commercial technology."
The Office of Naval Research (ONR), which is funding the project, is eager for an improved vehicle to aid Marines in the near term. GTRI researchers are working on a technology demonstrator vehicle called the ULTRA AP (Armored Patrol). The ULTRA AP will emphasize high-output diesel power combined with revolutionary armor and a fully modern chassis.
A more long-range project, the ULTRA 3T, will involve Georgia Tech Research Institute engineers in a ground-up rethinking of military vehicles to reshape the battlefield. The 3-ton ULTRA 3T will unite an array of advanced technologies in a single automotive package.
A more long-range project, the ULTRA 3T, will involve GTRI engineers in a ground-up rethinking of military vehicles to reshape the battlefield. The 3-ton ULTRA 3T will unite an array of advanced technologies in a single automotive package. Some of these technologies, such as anti-lock brakes and airbags, are commonly available on production automobiles. Others, such as computerized stability control systems and advanced power-generating capabilities, are truly cutting edge, researchers note.
"The Humvee is based on 1970s technology and has been incrementally modified until it's reaching the end of its capacity." Dudzik says. "The ULTRA design matches the best of modern commercial automotive technology coupled with NASCAR experience, novel design concepts, and research advances in lightweight armor to maximize fightability and protection."
In both vehicles, the GTRI/industry team is making improvements in three key areas.
* Safety with Performance. The vehicle uses onboard computers to integrate steering, suspension and brakes to provide an unparalleled level of mobility and safety, researchers say. The new vehicle's integrated chassis represents a leap ahead of the most advanced current production vehicles.
* Survivability. This factor involves a vehicle's ability to shield occupants from hostile action. The Humvee, designed during the Cold War, incorporated a light aluminum body so it could move fast on hilly European terrain. It has since added armor packages that increase protection, but they slow a fully armored Humvee to a speed that reduces its effectiveness and increases its vulnerability. The armor's extra weight also wears out vehicle parts more quickly, and the lack of air conditioning is a burden in hot desert terrain.
Improvised explosive devices (IEDs), Dudzik observes, are a major survivability concern. Mines accounted for more than 60 percent of vehicle losses in Vietnam and Desert Storm. Even a fully armored Humvee is vulnerable to mine blasts. The new Marine Corps vehicles must incorporate dramatically increased resistance to explosions.
* Power generation. Portable power is the third major issue GTRI is tackling. ONR wants the ULTRA 3T to provide up to a megawatt (one million watts) on the spot to power emerging battlefield concepts such as electro-static armor, which uses electricity for extra protection, and bunker-busting rail guns. Of course, such power could run command posts, communications gear and even power small villages.
With their mission to provide security to supply convoys, military police of the 2nd Military Police Battalion roll their Humvees through a course testing their ability to react to ambushes and to shoot on the move at a training range in the Kuwait desert Feb. 26, 2004.
Image: USMC Lance Cpl. Samuel Bard Valliere
ULTRA 3T plans call for a hybrid engine that combines diesel and electric power plants. That setup would not only aid power generation, but offer a silent electric mode when stealth is needed. Moreover, the new engine will give the ULTRA 3T the critical ability to move more swiftly out of harm's way. Pound for pound, today's diesels develop about twice the horsepower of the Humvee's 1970s engine. Plans call for an unloaded ULTRA 3T to go from zero to 60 miles an hour in 4.8 seconds.
GTRI and industry professionals form the right match to develop these complex vehicles successfully, Dudzik says. The team includes Scott Badenoch, an auto industry advanced development and racing professional; Tom Moore, former Chrysler vice president of Liberty Operations, the company's advanced engineering center; Walt Wynbelt, former program executive officer with the U.S. Army Tank-automotive and Armaments Command; and Dave McLellan, the former Corvette chief engineer for General Motors.
"We each bring something to the party," McLellan says. "The military does not design vehicles on a regular basis, so they really don't keep in-house expertise as current as those of us in the automobile industry. At the same time, the GTRI researchers bring their unique research perspective in materials science and the more cutting-edge physics and engineering elements."
A Humvee convoy pulls out of Camp Victory in Kuwait on March 2, 2004 en route to Iraq. Lance Cpl. Cody S. Braun, a heavy-equipment operator with 1st Force Service Support Group's Headquarters and Service Battalion, was on hand to add air to Humvee tires as soldiers departed.
Image: USMC Staff Sgt. Bill Lisbon
If preliminary plans hold, the ULTRA 3T will bristle with a welter of advanced "drive-by-wire" technologies designed to make driving the large, sophisticated vehicle safer than driving a sedan. Drive-by-wire is an emerging computerized approach that's analogous to the systems that allow advanced fighter and passenger aircraft to fly with more stability than any human pilot could achieve unaided.
"Drive-by-wire can enhance the capabilities of experienced as well as inexperienced drivers," Dudzik says. That's important because many Marines are teen-agers with limited driving experience facing the stress of a battle zone, he adds.
GTRI's ULTRA work is linked directly to "e-safety," an emerging automotive concept that combines computers and advanced technologies to make driving safer, McLellan notes. In e-safety, night driving systems and stability control add security, while radar systems -- already available in Europe -- actually slow vehicles automatically under certain conditions. Such augmented vehicles are especially important when the driver is very young, very old or impaired.
One ULTRA 3T concept that could find its way into everyday vehicles is 360-degree visibility -- a dashboard panorama available on an inboard screen. This approach would eliminate vulnerable windows in the ULTRA 3T, and it would also help many civilians, including the old and impaired who can't easily turn their heads. It should also help save fuel by eliminating wind-resisting outboard mirrors.
Designing a vehicle on a new sheet of paper is exciting, Badenoch says.
"It's very different from designing the next sport utility vehicle or even the next racing car," he adds. "There, you fundamentally know that everything has been done before and what the rules are. Here, we're taking a giant leap forward in technology to transform the battlefield."
Hybrid Porsche With Magnetically Loaded Flywheel Almost Won the 24 Hour Nurburgring Race
Magnetically Loaded Composite (MLC) technology was invented by engineers at British Nuclear Fuels and Urenco working on the design of uranium enrichment centrifuges.
Instead of using discrete permanent magnets to form the rotor of a flywheel’s integrated motor/generator, magnetic powder is mixed into the composite matrix. After the flywheel has been manufactured using filament winding, flash magnetisation of the integrated magnetic particles generates the required field configuration forming the rotor. With no large metallic structures in the MLC flywheel rotor, eddy current losses and heating are negligible resulting in very high electrical efficiencies. The lack of rotor heating gives MLC flywheels a unique advantage over other composite flywheel designs: they can be continuously deep-cycled at high power with no detriment to performance or reduction in life. The wholly composite MLC flywheel design also improves system safety: in the event of a failure, there are no metallic fragments requiring containment. In common with other flywheels, they can operate efficiently at extreme ambient temperatures – unlike chemical batteries and capacitors.
Greencarcongress - The 911 GT3 R Hybrid features an electrical front axle drive with two electric motors developing 60 kW each supplementing the 480-bhp (358 kW) four-liter flat-six at the rear of the 911 GT3 R Hybrid.
The flywheel generator itself is an electric motor with its rotor spinning at speeds of up to 40,000 rpm, storing energy mechanically as rotation energy. The flywheel generator is charged whenever the driver applies the brakes, with the two electric motors reversing their function on the front axle and acting themselves as generators. The flywheel is slowed down electromagnetically in the generator mode in order to supply up to 120 kW to the two electric motors at the front from its kinetic energy. This additional power is available to the driver after each charge process for approximately 6 - 8 seconds.
Williams Hybrid Power’s novel flywheel technology helped to power an impressive hybrid performance at this weekend’s Nürburgring 24hr race.
The 911 with its innovative drive concept, was able to gradually extend its lead through the high efficiency of its hybrid technology and its fuel consumption advantage. The hybrid car needed to pit every ten laps to refuel, whereas its rivals were forced to stop approximately every eight laps. “The hybrid system worked like a dream,” commented works driver, Richard Lietz.
The MLC Hybrid led the field of 200 cars (33 were Porsches) for eight hours until engine problems prematurely curtailed their impressive performance - just a tantalizing hour and a quarter from the finish line
Protean Wheel Motors and batteries provides easy retrofit of vans and cars to plug in hybrid
Protean Drive™ is a fully-integrated, direct-drive solution. Each motor has a built-in inverter, control electronics and software – no separate large, heavy and costly inverter required. Direct drive reduces part count, complexity and cost, so there is no need to integrate traditional drive train components such as external gearing, transmissions, drive-shafts, axles and differentials. Protean Drive™ packages easily inside a conventional wheel and can use the original equipment vehicle bearing.
A European-based Vauxhall Vivaro equipped with Protean Electric's fuel-saving electric wheel motors showed a 300 percent fuel economy improvement in hybrid mode on a European drive cycle fuel test.
Protean Electric, a leading global supplier of in-wheel electric motors, and Millbrook Proving Ground, one of Europe's leading vehicle test and demonstration centers, partnered to produce the Vivaro diesel hybrid.
Retrofitting is important because there are 1 billion cars and trucks on the road and there are only 60 million new cars and trucks each year.
"This Vivaro through-the-road hybrid vehicle demonstrates a practical, cost-effective and efficient way to retrofit a commercial vehicle into a plugin parallel hybrid by simply adding two in-wheel motors and a battery," said Protean Chairman and CEO Bob Purcell. "Our technology is uniquely designed for high-output, high-efficiency operations. Our in-wheel motors are unique in that they have the rotor on the outside and each motor's electronics on the inside. That simplicity of design creates more power density per motor and much simpler vehicle integration. It's the closest thing to a bolt-on hybrid system."
Protean Electric outfitted the front-wheel-drive Vivaro with a through-the-road hybrid conversion kit of two Protean Electric PD-18 motors attached to the rear axle. The two motors together provide torque assist of up to 1,180 lb.-ft. (1,650 Nm) peak and 740 lb.-ft. (1,000 Nm) continuous at the rear wheels.
In addition, Protean added a 21kWh battery, giving the vehicle more than 55 miles (90 km) of electric propulsion range and plug-in hybrid and electric vehicle capabilities. While operating in hybrid mode, the Vivaro measured 114 mpg (2.4 liters/100km) operating over the New European Driving Cycle (NEDC), over three times the fuel economy of the conventional vehicle.
The system can also deliver regenerative braking on the rear wheels with no modifications needed to the existing front brakes while retaining the vehicle's original engine and drive system. This high level of regenerative braking allows manufacturers to use a smaller battery size or extend the range with the same battery size.
The Vivaro retrofit also allows the driver the unique advantage of being able to switch between multiple operating modes: two- or four-wheel drive operation, IC engine-only drive, electric-only drive, or an electric torque assist Through-The-Road-Hybrid.
The vehicle underwent a rigorous testing regime jointly conducted by Millbrook and Protean Electric. Work is now underway to build a Vivaro Plug-In Parallel Through-The-Road-Hybrid test fleet for select fleet customers.
"Fleet operators should be lining up for a vehicle such as this that will provide more than a 65 percent reduction in fuel usage and CO2 emissions in a typical urban drive-cycle, while enabling electric-only operation for in-city low-emission zones such as London," Purcell said.
Looking for the next gram.
Munich. Even the most efficient internal combustion engine can only convert about one-third of the energy derived from fossil fuels into the mechanical kinetic energy needed to power a motor vehicle. Over the past few years BMW EfficientDynamics has made great improvements in engine efficiency, for example with technologies such as direct fuel injection, variable valve timing, exhaust-driven turbochargers, brake energy regeneration and the Auto Start Stop function. However, about 60 percent of the generated energy is still lost, half of it being exhaust heat, with the remaining half as heat absorbed by the engine cooling system. Finding ways of recovering this lost heat energy is one of the major goals being pursued by engineers working on BMW EfficientDynamics for the future. That is why the BMW Group is involved in several projects, each with different approaches to utilising dissipated heat energy, and at various levels – in research, pre-production and series development. Among the most promising innovations are the turbosteamer, thermoelectric generator, engine encapsulation and a waste heat exchanger for oil heating.
The Turbosteamer and Thermoelectric Generator (TEG) projects are focused on generating electric current from waste heat to improve overall engine efficiency, but each project follows a different approach and time frame. There is great potential for considerable fuel savings if the electrical energy required by all of the systems in an automobile can be produced using waste heat rather than relying solely on the vehicle's generator. This is another milestone behind the philosophy of BMW EfficientDynamics in achieving increased power and performance while reducing emissions and fuel consumption at the same time.
BMW turbosteamer – modelled after a power station.
In the Turbosteamer Project research and technology specialists of the BMW Group are working on a heat recovery system that is based on the principle of a steam process.
The process of recovering energy from waste heat is already practised on a large scale in modern power generation plants: large gas and steam power stations combine the principles of a gas turbine and a steam circuit to achieve a significantly higher level of efficiency. The gas turbine process is the first phase of the energy conversion and serves as the source of heat for the downstream steam cycle in the second phase.
The BMW turbosteamer is based on this two-stage stationary power generation method – but reduced in scale and design to form a component that can be used in modern automobile engines.
The first-generation turbosteamer – a maximalist approach.
Researchers proved the feasibility of this technology in December 2005 with the unveiling of the first-generation turbosteamer, which was based on a maximalist approach: they designed a dual-cycle system. The primary element was a high-temperature circuit that employed a heat exchanger to recover energy from the engine exhaust gases. This was connected with a secondary circuit that collected heat from the engine cooling system and combined this heat with the high-temperature heat from the primary circuit to create lower temperature heat.
When this design was laboratory tested on the four-cylinder petrol engines produced by BMW at the time, the dual system boosted the performance of these engines by 15 percent.
The turbosteamer today: smaller and simpler.
In order to further develop the system for use in series production, attention was given to reducing the size of the components and making the system simpler to improve its dynamics and achieve an optimized cost-benefit ratio. Thus researchers focused on designing a component having only one high-temperature circuit.
“A heat exchanger recovers heat from the engine exhaust, and this energy is used to heat a fluid which is under high pressure – this heated fluid then turns into steam, which powers an expansion turbine that generates electrical energy from the recovered heat,” explains Jürgen Ringler, Team Leader for Thermal Energy Converters at BMW Group Research and Technology. For the latest generation of the turbosteamer, engineers developed an innovative expansion turbine based on the principle of the impulse turbine, which offered many advantages in terms of cost, weight and size when compared to earlier concepts, and these are factors that are very beneficial when it comes to series production.
“We have made great progress toward achieving our original goal, which was to develop a system ready for series production within about ten years. When completed, this system will weigh only 10 kg to 15 kg and will be capable of supplying all of the electrical energy required by an automobile while cruising along the motorway or on country roads,” says Ringler. Under these conditions the developers are sure that the average driver will be able to reduce fuel consumption by up to 10 percent on long-distance journeys.
Initial integration of a mock-up system in the BMW 5 Saloon.
All of the system components developed on the test bench have been configured to form a module that can be integrated in vehicles. This has been done successfully by installing a mock-up system in the BMW 5 Saloon.
Considerable progress has also been made in the Thermoelectric Generator (TEG) Project that is also focused on series production of an energy-saving component. The two alternative systems developed to date differ in their positioning in the vehicle – one unit is designed for the exhaust system, while the other is intended for the exhaust gas recirculation system. The development phase focused on integrating units in the exhaust system has led to considerable component improvements, especially in terms of weight and size.
Electricity from waste heat – a space-age solution.
The thermoelectric generator converts heat directly into electricity. The engineers of the BMW Group basically refined a technology that has been used to power space probes for more than four decades by NASA, the aeronautics and space agency of the United States. The principle behind this technology is known as the Seebeck Effect, namely that an electrical voltage can be generated between two thermoelectric semiconducters if they have different temperatures. Since the percentage degree of efficiency of TEGs was rather low, this technology was considered unsuited for automotive applications. However, in recent years progress in the area of material research has led to discoveries that have improved the performance of TEG modules.
One principle – three generations.
The first step taken by engineers was to integrate a thermoelectric generator in the exhaust system to generate electrical current. The first such system was shown to the public in 2008 and delivered a maximum of 200 watts, which was relatively low in terms of power efficiency. But the use of new materials and improvements in the weight and size of the TEGs led to rapid new developments, so that the latest generation of TEGs installed in the exhaust are capable of generating 600 watts of electrical power, and it will not be long before the goal of 1,000 watts is reached as research progresses. The current prototype – a BMW X6 – was built as part of a development project funded by the US Department of Energy.
Then in 2009, the BMW Group unveiled an alternative development in this project. Rather than installing the TEG as a separate module in the exhaust system underneath the vehicle, engineers decided to integrate the TEG in the radiator of the exhaust gas recirculation system. In this configuration, customer testing has shown that 250 watts can be generated while CO2 emissions and fuel consumption are reduced by 2 percent at the same time.
What's more, this energy recovery system offers some interesting added benefits, such as supplying the engine or passenger compartment heating with additional warmth during cold starts. And the thermoelectric generator is the ideal counterpart for BMW EfficientDynamics Brake Energy Regeneration. While the brakes generate energy during deceleration and stopping, the TEG functions at its best when driving is really exciting – namely during acceleration. Researchers forecast that TEGs will lead to fuel consumption savings of up to 5 percent under real everyday driving conditions in the future.
The ideal combination: heat management and BMW EfficientDynamics.
While some features of BMW EfficientDynamics, such as brake energy regeneration or the Auto Start Stop function help reduce consumption when decelerating or during idling periods, intelligent heat management can do the same when the vehicle is being accelerated and driven. In the future, even before starting the car, insulation and encapsulation of the engine compartment will ensure that the temperature of the drive train is stabilised by residual heat, thus shortening the cold start phase. An exhaust heat exchanger will also keep gearbox oil warm to reduce friction and fuel consumption as well. And a TEG or turbosteamer will supply the vehicle's electrical systems with ample power, delivering benefits when it makes the most sense – while enjoying sheer driving pleasure!
Depending on the vehicle environment and driving habits, heat management can deliver measurable benefits for specific driving scenarios. For both short and long-distance driving various features can reduce fuel consumption. Insulation of the engine compartment, gearbox oil heating with exhaust heat exchangers installed with petrol engines, or the heating function of the exhaust heat exchanger for diesel engines are features that are well-suited for vehicles that are predominately driven over short distances. During longer journeys the thermoelectric generator or turbosteamer add to that. And by utilising synergy effects, heat management will play a major role in reducing CO2 emissions in the future.
We Design the Replacement for the Pentagon's Joint Light Tactical Vehicle
Yesterday, the U.S. Senate voted to cancel the Joint Light Tactical Vehicle. This new tactical vehicle would have replaced the Army and Marines' outdated Humvees, but the JLTV designs were too heavy and too expensive. With the program now on the chopping block, PM took matters into our own hands: We called defense experts who helped us design the ideal new military jeep. We call it the Popular Mechanics Light Tactical Vehicle.
BY JOE PAPPALARDO
September 14, 2011 6:00 PM
Curb Weight: 13,600 lb
Air-transportable: C-130 fixed-wing, CH-47 and CH-53 helicopters
Carrying capacity: Four crew
Armor: Bolt-on protection option for higher-risk operations
The Pentagon is having a devilishly hard time building a light tactical vehicle to replace the Humvee, which was introduced in the early 1980s to haul gear, ferry troops and conduct patrols. Contractors are vying to produce the next-generation all-purpose vehicle, called the Joint Light Tactical Vehicle (JLTV), for the Army and the Marine Corps. But with $300 million already invested—and at least $580 million more in projected development costs through 2015—the only options thus far have been expensive, overweight prototypes.
In February the Army's product manager of the JLTV program revealed to attendees of a National Defense Industrial Association wheeled-vehicle conference that each of the 21 JLTV designs submitted by contractors was as much as 1000 pounds too heavy. This degrades the vehicles' performance and, since JLTVs will be built to be carried by specific helicopters and fixed-wing aircraft, restricts their deployment. The cost is also rising. Replacing steel with lighter composites and metal alloys drives up the price; the JLTV options are already topping the $300,000 goal set by the Pentagon. Existing Humvees cost $75,000; with an extra armor kit, the price is around $200,000.
And now, in its 2012 defense spending bill, the Senate Appropriations subcommittee on defense has recommended terminating the Joint Light Tactical Vehicle program, citing “excessive cost growth and constantly changing requirements." Not willing to sit by while the defense industry that created the Jeep flounders, PM took action. We called on the nation's best military-vehicle designers to help us create the PMLTV, a rugged, menacing piece of machinery, if we do say so ourselves.
Read more: We Design the Replacement for the Pentagon's Joint Light Tactical Vehicle - Popular Mechanics
Bridgestone goes airless in tire concept for Tokyo show
December 3, 2011 by Nancy Owano
(PhysOrg.com) -- Visitors to the 42nd Tokyo Motor Show are to witness a new breed of airless tires from Bridgestone. Interest in the general press is already humming because of the material, design, and features of the Bridgestone debut on show. The concept tires use recycled thermoplastic, outside tread included. Fittingly colored green, the tires are being promoted for their green advantage of being completely recyclable.
The spokes are made of reusable thermoplastic resin. In design, interest is drawn toward the thermoplastic fins, staggered so that connections to the hub and the rim do not torque and there is no structural breakdown. The tires’ resin spokes radiate from rim to tread. They curve to the left and right to support vehicle loads.
Bridgestone is not the first to experiment with an airless tire concept. Observers point to Michelin’s debut in 2005 of its airless Tweel tires. These were seen with much interest as a novel departure from the traditional wheel hub assembly, though concerns were raised in some quarters about their being noisy and vibrations at high speeds. The name Tweel is a combination of the words tire and wheel. Michelin used polyurethane spokes arrayed in a wedge pattern.
In describing differences between the Michelin and Bridgestone concept, observers say a key contrast is in size of the ribs. Michelin’s tires were viewed as more suitable for military applications—this is not like the Bridgestone concept, which is suited for something more consumer-driven.
Another tire concept innovator has been Yokohama Rubber Co. Ltd. The company announced in October this year its airless tire concept which relies on mechanical rather than pneumatic support. Yokohama introduced its tire concept earlier this year at a design expo in Japan.
Bridgestone’s airless tires have a deeper structure of plastic ribs than either of the other two approaches, and it has a higher aspect ratio, according to Plastics News.
Obviously, the key benefit for the consumer will be seen in the fact that the Bridgestone tires cannot suffer punctures. On the other hand, these have a way to go before seeing car commercialization.
The tires are in prototype stage only and due for further evaluations. The company has tested the tires, nine inches across, on single seater electric carts in Japan.
Observers see similar uses, at this earlier level, as potential for use in motorized golf carts, lawnmowers and vehicles for the elderly.
U.S. Army's CERV puts a machine gun on a "green" military vehicle
By Sebastian BlancoRSS feed
Posted Feb 17th 2012 5:57PM
It used to be that we couldn't even find a picture of the U.S. Army's Clandestine Extended Range Vehicle (CERV) but times have changed.
At the 2012 Chicago Auto Show, the Army's Tank Automotive Research, Development and Engineering Center (TARDEC) is displaying the CERV, which uses a diesel-hybrid "Q-Force" powertrain from Quantum that Quantum says, "saves taxpayer dollars and – most importantly – saves Soldiers' lives."
With a top speed of 80 miles per hour and a "run-silent" range of eight miles (we assume this means all-electric range?), the CERV prototype can produce over 5,000 foot-pounds of torque and go up hills will up to 60 percent grades. It does all this while using 25 percent less fuel, Quantum says, and that's hugely important when you go invading countries and have to pay up to $400 a gallon to do so. The Army says that today's soldier uses an average of 22 gallons of gasoline a day. In World War II, it was one gallon a day.