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Some Experimental Investigations on Catalytic Combustion of Lean Burn S.I. Engine
Published June 01, 1992 by ISATA - Dusseldorf Trade Fair in United Kingdom
Event: ISATA 1992
Many efforts have been made to improve the performance, fuel economy, combustion characteristics and emissions of automotive S.I. engines. One of the effective methods to achieve this is the lean burn combustion. In a conventional S.I. engine it is very difficult to achieve lean combustion due to misfiring, partial and unstable combustion and low flame speeds. However these problems can be solved by providing a suitable combustion chamber shape, using higher ignition energy, using alternative fuels and providing catalytic coating in the combustion chamber to speed up combustion process. To date, catalysts have been used on motor vehicles solely for reducing exhaust emissions. However, if these catalysts are used in the combustion chamber, then the advantage of improved brake thermal efficiency in addition to lower emissions can be obtained.
Experimental investigations were made by coating copper as a catalyst by electro-plating process on the piston crown with lower and higher ignition energy systems at compression ratios of 8.5 and 12:1.
Test results indicate that the brake thermal efficiency is improved by 11% and brake power by 18.6%. HC and CO emissions are found to be lower. The lean misfire limit is extended from 23.5:1 to 25.5:1.