Development of Low NOx Emission Diesel Engine by Impingment of Fuel Jet
This study is concerned with development of a new type of Diesel engine by impingement of fuel jet. The impinging part is installed on the cylinder head (OSKA-DH), against which the fuel jet is injected to spread and form fuel-air mixture. As a fundamental study on the mixture formation process, the observation of the impinged fuel jet was studied by using a pressurized vessel. High-speed combustion photographs of the OSKA and DI Diesel engine were also taken by using the experimental transparent engine. A single cylinder 4 stroke cycle prototype OSKA-DH engine (ø 118 x 108 mm) was developed. Pintle type single hole fuel injector is used and relatively low opening pressure of 15.3 MPa is employed. The re-entrant type combustion chamber and relatively high compression ratio of 20.4: 1 are employed. Experiments with a single cylinder proto-type engine showed that the lower NOx and smoke emissions compared with the conventional DI diesel engine.