Development of a Direct Injected Neat Methanol Engine For Passenger Car Applications

Abstract

<div class="htmlview paragraph">Despite progressively stricter emission regulations, the harmful effects on the environment resulting from internal combustion engine powered vehicles. especially in heavily populated urban areas, has increased. Alternative fuels, especially neat methanol, have new found importance due to their environmental benefits.</div> <div class="htmlview paragraph">Through a research program sponsored by the U.S. Environmental Protection Agency, a direct-injected (DI) methanol glow plug engine is being developed and integrated into a passenger car. The base engine for this project is a prototype DI diesel engine, which is currently under development by Volkswagen AG. The methanol DI engine displaces 1.9L and is equipped with a turbocharger, an intercooler, and exhaust gas recirculation (EGR). The engine demonstrates basically the same favorable efficiency of a small DI diesel engine in combination with very low NOx and particulate emissions. By utilizing a specially developed oxidation catalyst, HC and aldehyde emissions are likewise maintained at a very low level.</div> <div class="htmlview paragraph">The concept of the DI methanol engine and details of the basic investigations to optimize the glow plug assisted combustion system are presented. Emphasis is placed on the development of the engine with respect to very low unburned fuel emissions, in combination with lowest possible NOx emissions. Therefore, the influence of EGR, intake air preheating, and an oxidation catalyst are presented. Possibilities to reduce HC Emissions under low-load conditions, which are critical with respect to FTP-75 testing, are also demonstrated.</div> <div class="htmlview paragraph">The operational behavior and emission characteristics of the methanol glow plug assisted engine are compared to those of a prototype DI diesel passenger car engine.</div> <div class="htmlview paragraph">The integration of the <b>methanol</b> engine into a passenger car, including initial chassis dynamometer test results, are discussed in combination with an evaluation of future development requirements for this engine.</div> <div class="htmlview paragraph">Finally, the planned evaluation of the engine in a passenger car. in terms of exhaust emissions and low ambient temperature cold <b>startability</b>, is also discussed.</div>