2324 CFD Analysis of Performance Improvement in a Longer Stroke Gas Engine
Details
Expansion of stroke/bore ratio has a great potential to improve thermal efficiency in co-generation engines. The factors related on thermal efficiency in gas engines with three stroke/bore ratios were analyzed with CFD engine code. Improvement in indicated thermal efficiency with larger stroke/bore ratios was obtained due to improvement in the degree of constant volume heat release and decrease in cooling loss in wide ranges of excess air ratio and engine speed. The degree of improvement with expansion of stroke/bore ratio from 1.0 to 1.5 is more significant than from 1.5 to 2.0. The degree of constant volume heat release improves with longer strokes due to shorter flame propagation distance and increase in combustion speed with increasing turbulence of charge gas in cylinder.
