Honda develops greener VTEC
Honda has announced an improved version of its VTEC (Variable Valve Timing and Lift Electronic Control System) technology with the development of the 2.4-liter "Advanced VTEC engine," which achieves high performance along with improved fuel economy and lower emissions. The new engine combines continuously variable valve lift and timing control with the continuously variable phase control of VTC (Variable Timing Control). Honda plans to release a production vehicle equipped with the new engine within three years.
This new system permits optimum control over intake valve lift and phase in response to driving conditions, achieving improved charging efficiency for a significant increase in torque at all engine speeds. Under low to medium load levels, the valves are set for low lift and early closure to reduce pumping losses and improve fuel economy.
In combination with optimized intake components, the technologys result in a 13 percent improvement in fuel economy. The new engine is also exceptionally clean, with exhaust emissions that meet both U.S. Environmental Protection Agency LEV2-ULEV regulations and Japanese Ministry of Land, Infrastructure and Transport requirements for Low-Emission Vehicles, with emission levels 75% lower than those required by the 2005 standards (based on Honda calculations).
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Honda develops new diesel to meet U.S. regulations
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Honda has developed a next-generation diesel engine that reduces exhaust gas emissions to "a level equal to a gasoline engine," the automaker said today. The engine employs a new NOx catalytic converter that enables a great reduction in NOx emissions sufficient to meet stringent U.S. Environmental Protection Agency (EPA) Tier II Bin 5 emissions requirements. This catalytic converter features the world�s first innovative system using the reductive reaction of ammonia generated within the catalytic converter to "detoxify" nitrogen oxide (NOx) by turning it into harmless nitrogen (N2).
The new catalytic converter utilizes a two-layer structure: one layer adsorbs NOx from the exhaust gas and converts a portion of it into ammonia, while the other layer adsorbs the resulting ammonia, and uses it later in a reaction that converts the remaining NOx in the exhaust into nitrogen (N2). Ammonia is a highly effective reagent for reducing NOx into N2 in an oxygen-rich, lean-burn atmosphere. This ability to generate and store ammonia within the catalytic converter has enabled Honda to create a compact, lightweight NOx reduction system for diesel engines. The system also features enhanced NOx reduction performance at 200�300�C, the main temperature range of diesel engines.
Honda designed the catalytic converter for use with its 2.2 i-CTDi diesel engine, which has earned widespread praise for quiet, clean operation and dynamic performance since its introduction in 2003 on the European Accord model. By further advancing combustion control, the 2.2 i-CTDi delivers cleaner exhaust to the NOx catalytic converter. Honda achieved this by optimizing the combustion chamber configuration, reducing fuel injection time with a 2,000-bar common rail injection system and boosting the efficiency of the EGR (exhaust gas recirculation) system. Thanks to these improvements, Honda has reduced the amount of NOx and soot normally found in engine exhaust, while increasing power output.
Along with developing superior technology for cleaning exhaust gas, Honda plans to address other technical challenges in developing clean diesel engines, such as handling diesel fuels with different cetane numbers and meeting U.S. On-Board Diagnostic System requirements. Honda plans to introduce its next-generation diesel engine in the U.S. within three years.
Gasoline engines presently employ three-way catalytic converters that offer NOx reduction rates as high as 99%, but this performance is possible only at the stoichiometric air-fuel ratio. In the oxygen-rich environment of a lean-burn diesel engine, three-way catalytic converters only reduce NOx levels by approximately 10%. Honda�s new catalytic converter efficiently reduces NOx in a lean-burn atmosphere, enabling diesel engines to rival gasoline engines in cleanliness. The compact system is also easy to install in passenger vehicles.
http://images.leftla...p25-honda-1.jpg * 1. During lean burn operation, the NOx adsorbent in the lower layer adsorbs NOx from the exhaust gas.
* 2. As needed, the engine management system adjusts the engine air-fuel ratio to rich-burn, wherein the NOx in the NOx adsorption layer reacts with hydrogen (H2) obtained from the exhaust gas to produce ammonia (NH3). The adsorbent material in the upper layer temporarily adsorbs the NH3.
* 3. When the engine returns to lean-burn operation, NH3 adsorbed in the upper layer reacts with NOx in the exhaust gas and reduces it to harmless nitrogen (N2).
Top Gear put on hold; Hammond walks, makes jokes
Top Gear presenter Richard Hammond took his first steps Saturday following a 300 mph accident that left him with "significant" brain trauma last week. Hammond has been moved to a general ward, where he has been talking and sharing jokes. Meanwhile, there is building concern over the future of the Top Gear TV series following the BBC's decision to postpone the new season of the show. Hammond and Jeremy Clarkson are reportedly concerned the organization could cancel the show all together. Writing in the Sunday Times, Clarkson said there are "swarms of bureaucratic bluebottles [�] nibbling away at the crash site on a York airfield, desperately trying to find some reason why Top Gear should be banished from our screens." At the same time, producer Andy Wilman has threatened to quit if the BBC attempts to "tone down" the show.
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