Improving Performance of Compressed Natural Gas Fueled Passenger Car Engine by Addition of Hydrogen

Hydrogen is a clean fuel that can be used as sole fuel or blends with compressed natural gas (CNG) in the spark ignition engines. Blending of hydrogen in CNG improves the burning velocity and calorific value of CNG. Engine tests were carried out using CNG and optimized fuel blend of 18%HCNG for comparing the engine performance and emissions behavior. Marginal improvement in engine performance (up to 2%) and significant reduction in emissions with18%HCNG compared to neat CNG. The brake specific fuel consumption was 5% lesser compared to CNG. Replacement of methane by hydrogen in the 18%HCNG blend reduced the HC emissions by ~20% and NOx emissions was increased by ~ 10-20% compared to CNG. 18% HCNG decreased the methane emissions up to 25% compared to CNG. The investigation showed that 18% HCNG has given better performance and emissions compared to CNG.