An Investigation of Effect of Adding Hydrogen on Natural Gas Engine Performance and Estimating the Appropriate Ignition Timing for Optimum Point

In this paper, the effect of adding hydrogen to the performance of D87 gas engine has been discussed. The base system is an engine with power of 1000 kW and rotational speed of 1500 rpm which by changing the fuel system and compression ratio from 15 to 11.5 it is modified to a gas engine. Among many additives, hydrogen with its unique criteria seems to be the most promising additive which can significantly reduce fuel consumption and harmful emissions in internal combustion engines. It seems, the hydrogen is the best additive among various cases, which can greatly reduce fuel consumption and harmful emissions in internal combustion engines. Here the effect of adding different mass ratios of hydrogen fuel to natural gas fuel flint to see a change in behavior of flint fuel is examined. In this paper, the hydrogen mass ratios of 0, 0.002, up 0.014 are considered which is equivalent to adding 50% of chamber imported energy and according to these points the optimal point has been determined based on performance and pollution viewpoints. By considering these viewpoints, the optimal point of 0.006 for mass ratio of hydrogen which is equivalent to adding approximately 18% energy to the combustion chamber is achieved. Then the appropriate ignition timing for 0.006 of mass ratio with advance and retard of the ignition timing is estimated. The results show that 3 degree for advance of ignition timing is suitable for this mass ratio.