Abstract
This paper describes a new four-valve cylinder head for the Ricardo Hydra research engine. This cylinder head was built for a research project on the new combustion chambers for heavy duty spark ignition engines operating on natural gas, conducted at the Department of Mechanical
Engineering, University of British Columbia, Canada. The new four-valve cylinder head will allow the determination of the optimum level of turbulence inside the combustion chamber, which originates from intake-generated swirl and tumble gas motion and their effects on the combustion process in engines fueled with natural gas.
The results of research on the optimization of a fast, lean-burn combustion system for spark-ignited natural gas engines that meet emission regulations without the use of exhaust gas clean-up equipment are also presented. A family of squish-jet pistons was developed and tested over a wide range of air-fuel ratios using full-load operating conditions; these results are also presented and discussed.