Combustion parameters optimization of a diesel/natural gas dual fuel engine using genetic algorithm

The objective of this study is to optimize the diesel injection parameters, operating parameters and the combustion system of a diesel/natural gas fueled dual fuel engine simultaneously by applying the genetic algorithm. The indicated specific fuel consumption, NOx and CH4 emissions are selected as the optimization objectives. It is shown that almost all the solutions can meet the EURO VI emission limit of the Soot. However, only partial solutions satisfy the EURO V NOx emission limit. More open combustion chambers are chosen than the re-entrant combustion chamber on the Pareto front. A wide range distribution of the combustion bowl radius is found on the Pareto front. However, the diesel fuel spray angle, swirl ratio, EGR (Exhaust Gas Recirculation) rate and compression ratio are gradually concentrated near several optimal points. The response surfaces of ISFC, CH4 and NOx emissions for injection timing vs. EGR rate and spray angle vs. swirl ratio for all the calculated Pareto citizens are achieved.