Author(s)

Zhou Yang, Zhongshu Wang, Hengyi Yuan and Hongzhi Wang

Corresponding Author

Zhou Yang

ABSTRACT

Based on the common issues for diesel / natural gas dual fuel engine existing in the key technologies, the main purpose of this research is to solve the low thermal efficiency and high CH4 emissions under low load conditions. In order to improve the performance of economic and reduce CH4 emissions, the combustion chamber has been optimally designed to enhance cylinder turbulent flow and improve the mixed gas combustion. The numerical simulation platform is established by using the commercial software STAR-CD and its validity is verified. A new type of combustion chamber has been designed to improve the flow in the cylinder and the combustion rate through analyzing the variation of micro combustion parameters in the cylinder under the original condition (1335 r/min, 218N•m). The results show that compared to the original engine, the new combustion chamber can effectively enhance the turbulent flow in cylinder, the maximum explosion pressure increases by nearly 25% and the natural gas residual rate reduces from 28.6% to 0.5%. The optimal design method has improved the combustion quality and the economy and emissions performances greatly.

KEYWORDS

Diesel / natural gas dual fuel, combustion chamber, engine