Consequences of suplementing the HHO gas and CNG with EGR on diesel engine characteristics

Abstract

Water electrolyzed hydroxyl gas (HHO or Brown gas) and compressed natural gas (CNG) are the important and promising alternatives to the pure fossil fuels. The global concern is about GHG emission in the environment and ambient air pollution steered by mass consumption of fossil fuels in automobile industries and power sectors. In this study, the combustion, performance and emission characteristics of HHO gas and CNG mixtures supplied to intake manifold of compression ignition engine using diesel as a pilot fuel are studied. The same investigations are repeated with various exhaust gas re-circulation (EGR) proportions to study the impact of EGR on multi fuel mode (diesel + HHO gas + CNG) in a Diesel engine. The multi fueled engine performance, combustion and emission parameters are presented and compared with graph and analytical discussion. The results indicated that at full load, the NOx emission decreased by 4% (without EGR), 18% (with 10% EGR) and smoke density decreased by 78% with multi fuel mode comparing to the pure diesel operation at constant speed of 1500 rpm. Also more enhanced performance by improving the brake thermal efficiency by 17%, reducing the brake specific energy consumption by 19%, resulted better fuel economy, and power due to better combustion.