STUDY ON HEAT RELEASE RATE BY COMBUSTION IN DIESEL ENGINE

Diesel기관의 연소에 의한 열발생율의 연구

This paper dealt itself with the relation of the heat release rate with crank angle in combustion process by adjusting the injection time, injection amount and engine speed of diesel engine. The result of test were obtained by analyzing indicator diagram of KUBOTA 2LKE diesel engine, where the indicator was used Tertronix oscilloscope. The combustion period of diesel engine is composed of premixed burning time and combustion controlled time. The larger the premixed burning region, the higher efficiency was obtained with the higher maximum pressure than at the time of the normal smooth operation. The longer the combustion controlled time, the lower the maximum pressure than the period of the normal operation, but the efficiency was decreased. The region of premixed burning was principally controlled by injection delay, but combustion controlled time was affected when oxygen and fuel were mixed. Efficiency of engine was increased at the time of earlier injection time under the constant injection amount, and engine speed, but the pressure increasing was observed higher than the efficiency increasing.

Diesel 기관의 연소는 매우 복잡한 현상이다. 이 복잡한 연소과정을 각운전조건하에서 구한 열발생율에 의해 해석했으며 그 결과 다음 사항이 밝혀졌다. 1. Diesel기관의 연소기간은 예혼합기연소기관과 황산연소기관으로 나누어 생각할 수 있다. 2. 예혼합기연소부분이 클수록 효율은 양호하나 최고압력이 높아져 정숙한 운전이 되지 못하고 확산연소기간이 길수록 운전은 정숙하나 효율은 떨어지고 배기온도는 상승한다. 3. 예혼합기 연소부분은 주로 발화지연에 지배되나 확산연소기간은 산소의 확산에 지배된다. 4. 실험범위내에서 기관의 효율은 분사량과 회전수가 일정하면 분사시기가 빠를수록 효율은 증가했으나 압력의 상승은 효율의 증가보다 높았다.