Seiko Kono

Study of the stratified charge and stable combustion in DI gasoline engines

A new combustion method for DISC engines was developed. It has a double structure combustion chamber known as “Caldera”. This method makes possible a perfect un-throttling operation, and a fuel consumption equal to a diesel engine is achieved. In the output of the DISC engine, a stoichmetric combustion and a high torque are achieved by controlling the fuel injection timing with an electro-magnetic injection device. With regard to emission regulations, a heavy EGR including residual gas greatly decreases NOx and HC emissions simultaneously.

Prediction of ln-Cylinder Flow and Spray Formation Effects on Combustion in Direct Injection Diesel Engines

The study of the phenomena of in-cylinder flow, spray and combustion by measurement and calculation has been vigorously pursued, because thermal efficiency and emissions of the D.I. diesel engine are influenced by them. To investigate the effects of in-cylinder flow on spray and combustion, the D.I. diesel engine simulation model has been developed. This model is composed of in-cylinder flow, spray and combustion models. In the spray model, spray non-uniformity is considered, and physical and chemical processes are considered in the combustion model. The effects of swirl, number of nozzle holes, injection pressure and squish area on thermal efficiency and emissions have been investigated, and the existence of optimum values of these parameters against thermal efficiency have been predicted and these predictions have been verified by measurement.