Experimental investigation on in-cylinder pressure and emissions of diesel engine with port injection hydrogen system

Abstract

Towards the efforts of increasing the performance and reducing pollutant emissions of diesel engine, port injection gaseous fuel system is one of the solutions and it is applicable for dual fuel combustion engines. In this study, series of experiments were carried out to study the effect of continuous port injection hydrogen gas on in-cylinder pressure and emissions of unmodified single cylinder diesel engine. Injection of hydrogen results an increase in in-cylinder peak pressure in the range of 5 to 23 bars and exhaust gas temperature in the range of 3.1% to 10.2% throughout all engine speeds. There were also increases in NOx, CO and CO2 emissions due to presence of hydrogen ranges between 50 to 200 ppm, 420 to 760 ppm and 1.1% to 4.2% (by volume), respectively. On the other hand, continuous port injection hydrogen addition in diesel engine showed reduction of hydrocarbon (HC) at the average of 15 ppm and O2 emissions at the average of 6% (by volume).