Experimental Investigation on Natural Gas Injection to Minimize Abnormal Combustion and Methane Slip in the Diesel - Natural Gas Dual Fuel Engine at Low Load

Abstract

Natural gas proposed to replace liquid fossil fuels in high-speed engines, which were considered a cleaner fuel, lower emissions, and more efficient. However, natural gas had several disadvantages. Natural gas was thought to cause abnormal combustion and methane slip phenomenon as the primary fuel in the dual-fuel engines. This experiment has investigated the natural gas injection on a dual-fuel engine. This study aims to minimize the appearance of abnormal combustion phenomena, such as knocking, misfiring, and pre-ignition, while reducing methane slip. Investigations were carried out to see how injection timing, duration, and natural gas intake pressure on combustion performance at low load. This study concluded that the injection timing should be reversed near the intake valve closure by adjusting the injection duration or reducing gas pressure. It affects to reduce the abnormal combustion and methane slip in low load. The injection timing effect was more dominant on combustion operations than the duration injection and intake gas pressure setting to reduce methane slip and avoid abnormal combustion in diesel – natural gas dual-fuel engine.