Investigation of Hydrogen Enrichment in Diesel Engine Performance, Emission and Combustion Characteristics
Abstract
This research work studied the effect of introducing hydrogen on engine characteristics in a diesel engine in the aim of replacing the conventional diesel fuel partially. The favourable properties of hydrogen fuel, such as its high flame velocity and calorific value, make it to utilize in combination with diesel fuel in a dual fuel mode of operation. In this experiment, hydrogen was inducted into the inlet manifold of a diesel engine along with intake air. The experiment was performed at a constant engine speed of 1500 rpm for various load conditions. By using a digital volume flow metre, hydrogen was injected at three different volume flow rates, namely 3, 6, and 9 lpm. Engine performance, emission, and combustion parameters were evaluated and compared to sole diesel fuel operation at varied hydrogen flow rates. The result revealed that hydrogen enrichment increased brake thermal efficiency and decreased brake specific fuel consumption when compared to the sole diesel operation. With increase in hydrogen flow rate, hydrocarbon, NOx emission and carbon monoxide emissions were reduced in comparison to sole diesel operation under all load situations. In comparison to sole diesel operation, hydrogen flow rate increases the rate of heat release and cylinder pressure. Among the evaluated H2 flow rates, 9 lpm is found to be the best, demonstrating enhanced performance, emission, and combustion characteristics.
