Effect of Supplementing Water Electrolyzed Hydroxyl Gas and Exhaust Gas Recirculation in the Combustion Process of a Compression Ignition Engine

Abstract

In the current state of affairs, the global concern is about greenhouse gas emission into the environment and ambient air pollution driven by massive consumption of fossil fuels by the various automobile and power generating sectors. One of the most excellent solutions to control the above concern is to develop and employ carbon-neutral fuels in internal combustion engines. Water electrolyzed hydroxyl gas (HHO gas) is the imperative and promising alternate fuel to pure fossil fuels. In this study, the performance, combustion, and emission characteristics of a 3.7 kW single cylinder four stroke CI engine enriched with HHO gas supplied to the intake manifold with the constant speed of 1500 RPM using diesel as a pilot fuel are studied. In this investigation, HHO gas was generated through the electrolysis of water and utilized to exterminate the handling and safety-related issues originated by compressed hydrogen. The examinations are repeated with HHO blend of 5, 10 and 15% with various Exhaust Gas Recirculation (EGR) proportions to study the impact of HHO gas and EGR on dual fuel mode of diesel engine. The dual-fuelled (diesel + HHO gas) engine’s performance, combustion, and emission parameters are presented and compared in both analytical and graphical approaches. The results obtained at full load conditions are exhibited and compared with neat diesel operation. The brake thermal efficiency is higher by 9.6% for 15% HHO gas without EGR. NOx emission is almost similar for 10% HHO gas with 10 and 15% EGR. Smoke and greenhouse gas emissions are lower by 33.3% and 13.2% respectively for 15% HHO gas without EGR. Reduction in CO and HC emissions are noticed in dual-fuel operation.