소형 선박용 디젤엔진에서 엔진초기화 세팅을 통한 연소성능 및 배기배출물 개선에 관한 연구

Abstract

Tugboats that sail along a coast may experience poor engine combustion performance due to frequent entry and departure and frequent change of the ship’s speed. Decrease in combustion performance may cause an increase in specific fuel consumption and an increase in harmful exhaust emissions. Consequently, the engine maintenance cycle may be shortened, and its maintenance cost may increase. An initialization method that returns a small marine diesel engine to the state of a new engine needs to be employed to improve the combustion performance and reduce exhaust emissions. This method involves adjusting the matching of the exhaust turbocharger initialization, fuel injection timing, and fuel injection amount. By using this method, it is possible to optimize the engine by considering its future load range. This study measured and diagnosed the combustion condition of a small ship (tugboat) equipped with a 4-stroke diesel engine, which is currently operated. The methods to improve combustion performance and reduce exhaust emissions were then suggested. When the engine performance was improved through engine initialization, the maximum compression pressure increased by 34.9%, maximum explosion pressure by 24.7%, indicated mean effective pressure by 10.9%, engine output by 20.0%, and specific fuel consumption by 4.2%. Additionally, the exhaust gas temperature decreased by an average of 39.2 °C. The result of exhaust emission measurement revealed that particulate matter decreased by 55.8%, carbon dioxide known as greenhouse gas by 12.5%, carbon monoxide by 74.4%, and nitrogen oxide by 4.4%.