Effect of Diesel Engine Converted to Sequential Port Injection Compressed Natural Gas Engine on the Cylinder Pressure vs Crank Angle in Variation Engine Speeds

The diesel engine converted to compressed natural gas (CNG) engine effect is lower in performance. Problem statement: The hypothesis is that the lower performance of CNG engine is caused by the effect of lower in engine cylinder pressure. Are the CNG engine is lower cylinder pressure than diesel engine? This research is conducted to investigate the cylinder pressure of CNG engine as a new engine compared to diesel engine as a baseline engine. Approach: The research approach in this study is by convert the diesel engine to multi point injection dedicated CNG engine. The engine conversion is by changed the diesel fuel to CNG fuel, changed the injection fuel system, changed the ignition system, modified piston to reduce the compression ratio and added throttle to in intake port. If the development is completed, the engine cylinder pressure is investigated. In this study, the cylinder pressure is investigated in 7 cases engine speed from 1000 to 4000 rpm with range in 500. Results: The research results are cylinder pressure and maximum pressure of CNG engine compared to diesel engine in 1000 to 4000 rpm engine speed. Conclusion/Recommendations: Effect of diesel engine converted to CNG engine is decrease the cylinder pressure. The further research is needed to find the higher performance of CNG engine.