Koji Imoto

Reduction of Fuel Consumption in IDI Diesel Engine.

In order to reduce fuel consumption in an indirect injection (IDI) diesel engine, a new combustion system that increases the degree of constant volume of heat release and reduces heat loss was investigated using a four-cylinder diesel engine with 98 mm bore and 98 mm stroke. As a result, the new combustion system which consists of a new combustion chamber with a refined jet passage in which the jet passage angle inside the main chamber is smaller than that inside the prechamber, an enlargement of the jet passage area, a miniaturized injection nozzle with a reduced needle diameter and a plunger with an enlarged diameter, was proven to increase the degree of constant volume of heat release, reduce heat loss, and reduce fuel consumption over the wide range of engine operation.