الفهرس | Only 14 pages are availabe for public view |
Abstract The limited crude oil reserves together with the increasing concern about environmental protection, pushed scientists to research in alternative fuels for internal combustion engines as CNG, LBG, HCNG, H2 etc. With the aim of reducing fuel consumption and increasing engines efficiencies, hydrogen is often thought of as the ideal alternative fuel for internal combustion engines as it has clean burning characteristics and doesn’t produce toxic products because its main product is water. Hydrogen is the most abundant element on earth but its current use is as a fuel additive to improve the combustion of HC fuels like CNG due to its high burning velocity. Studying the impact of hydrogen enriching of CNG fuel on performance and emissions parameters of automotive engine is the object of this research. For this purpose a test rig has been constructed consisting of a1.5 Liter Hyundai carburetor engine coupled with a water dynamometer to measure power, torque, BSFC, BTE parameters and exhaust gas emissions using measuring facilities consisting an orifice plate equipped with U-tube manometer to measure induced air volume flow rate, calibrated digital load cell to measure mass flow rate of consumed fuel and AGS -688 5-gases gas analyzer to measure emissions parameters and engine speed. The engine was fitted to operate on gasoline, CNG, (10%H2 /90%CNG), (20%H2/ 80%CNG) and (30%H2/ 70%CNG) by volume mixtures and was tested in two different modes of operation such as steady state condition with WOT and variable speed range from 1500 rpm to 4500 rpm and at the constant speed of 2000 rpm with variable load of 25% to 75% of engine full load. It was found that: -Adding hydrogen to compressed natural gas fuel improves power, torque, BSFC, BTE of around 21.8%, 10%, 15.1%, 11% respectively and emissions except NOx emissions for full load test relative to those of pure CNG fuelled engine. |