The Combustion And Emission Research Of Turbocharged And Inter-Cooled On CA4SH CNG Engine

With the decreasing of petroleum resource, it became an urgent affair to lookfor alternative fuel now. The natural gas has attracted a lot attention due to its advantage in cost and emission. Developing natural gas engine is one of effective means to solve the traditional energy crisis.The main work includes:1. The test-bench is set up. And the experiment scheme is designed. engine turbo-charged system, as well as the structure of EGR system design and installation.2. The studies showed that as air excess factor(λ)increased, in-cylinder mixture concentration became leaner, the propagation of flame front became slower, the combustion delay duration and the main duration became longer, maximum cylinder pressure decreased, heat release ratio became lower. The combustion cycle variability was higher. NOx emission reduction after the first increase in theλnearly to 1.1 at the maximum. Whenλincreased from 1.0 to 1.1, significantly reduce CO emissions to the minimum. HC emission is relatively stable, atλmore than 1.5, the HC rising sharply.3. With the ignition advance angle increase, the biggest increase pressure on the outbreak, Combustion high rate of speed combustion, thermal efficiency, complete combustion, combustion stability improved, after burning less than decrease gas consumption, lower temperature Pai, CO little effect on NOx emissions increased dramatically, lower HC emissions. However, the increase caused by the ignition advance angle NOx emissions can be increased through an appropriate increase to reduce excess air ratio.4. With the increasing rate of EGR, high coefficient of residual gas burning to deteriorate and reduce in-cylinder combustion temperature, resulting in-cylinder pressure, heat release rate of decline in economic decline of HC and CO emissions increased slightly, NOx substantial decline in emissions.