저온 디젤 연소를 이용한 직접분사식 디젤엔진의 운전영역 제시

Abstract

This study investigates the low temperature diesel combustion with influence of ultra-high exhaust gas recirculation and injection pressure on the exhaust emissions and operating range in a 5-cylinder 2.7L direct injection diesel engine. Simultaneous reduction of nitrogen oxide and Soot emissions were achieved using the ultra-high EGR which can reduce in-cylinder temperature. However, higher hydrocarbon and carbon monoxide were also observed at the same time. And when adopting EGR of over 65% or oxygen content of under 9%, soot emission were re-increased due to in-complete combustion. When engine operation speed was low, soot emission was reduced as increasing the injection pressure because fuel was easy to atomize. The operating range of low temperature diesel combustion was reduced at the high load engine operation. And it was observed similar BSFC value at the low load engine operation.