الفهرس | Only 14 pages are availabe for public view |
Abstract In the present time the use of gaseous fuels in Internal Combustion Engines is considered one of the main solutions for the problems of liquid hydrocarbon fuel depletion and environmental pollution. Natural gas is the most prominent as alternative fuel because of its high quality, less expensive, large resources in Egypt and other countries. The present work gives an experimental investigation and comparative study of using both LPG (liquefied petroleum gas) and CNG (compressed Natural gas) in a diesel engine. One type of diesel engine is modified to operate as : 1- spark ignition engine using LPG or CNG 2- Diesel engine using dual fuel ( eNG or LPG) with liquid fuel, Performance test and exhaust gas analysis are measured in each case for comparative study. It was found that the use of gaseous fuel in modified diesel engine will reduce the maximum power by 20%, but the thermal efficiency will increase by about 5%. The use of LPG or eNG in spark ignition engine has no considerable effect on maximum power but the efficiency is lower in the case of LPG. In case of diesel engine using both liquid and gaseous fuels the percent of energy released from the gaseous fuel depends mainly on the power to prevent engine knock The use of gaseous fuel is more economic at higher loads and there is a suitable ratio at each load. The use of LPG or eNG has no considerable effect on the concentration of pollutions in the exhaust gases. |