When methanol is used as fuel for internal combustion engines, formaldehyde and unburned methanol emissions can be a problem. To overcome this shortcoming, an engine with the active thermo-atmosphere combustion (ATAC) system was proposed along with improvements in heat-insulatine performance and the realization of high-temperature combustion by using ceramics for the combustion chamber walls. The combustion and emissions characteristics of this ceramic low heat rejetion (LHR) methanol ATAC engine were investigated. Combustion performance was compared between operation with methanol and gasoline. When methanol was used, it was seen that the ATAC operation region was widened considerable. Also, a reduction in aldehyde emissions was achieved, due to the high-temperature operation of the combustion chamber. However, efficiency deteriorated at times due to early self-ignition timing. This was overcome by the use of lean fuel-air ratios, which resulted in both a reduction of NO(x) and an improvement in fuel consumption. With a premixed fuel supply system, wall surface ignition was unavoidable for combustion chamber surface temperatures greater than 800 K (527 Grad C). Wall surface temperature swing and instantaneous heat flux increased substantially with ATAC operation under these conditions.
Combustion and emissions of low heat rejection ceramic methanol ATAC engines
Verbrennung und Emission von wärmeisolierten, keramischen Methanolmotoren mit aktiver thermo-atmosphärischer Verbrennung
JSME International Journal, Series B (Fluids and Thermal Engineering) ; 39 , 1 ; 176-184
1996
9 Seiten, 26 Bilder, 6 Quellen
Article (Journal)
English
SAE Technical Papers | 1979
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