LPG as an alternative fuel for dual fuel compressionignition engine

The merits of diesel engines compared to other internal combustion engines are lower specific fuel consumption, and unburned hydrocarbons emissions, due to the overall lean combustion and better energy release efficiency due to controlled nonhomogeneous combustion at high pressures. Diesel engine is therefore an attractive option to reduce CO emissions from automobile engines and to counter greenhouse gas effects. On the other hand, because of the existence of rich high temperature zones leading to fuel pyrolysis, Diesel engine is very likely to produce particulate emission in the exhaust gas. As the intensive use of diesel engines causes detrimental effects on environment and health, more stringent emissions standards have been imposed, which challenge the viability of diesel engines. There are several strategies that may be employed to reduce the emissions, namely, refinement of treatment, usage of particulate traps, and employing alternative fuels like LPG, CNG etc. Liquefied Petroleum Gas (LPG) is paid to attention as an useful alternative. LPG is thought to be a major energy resource of the future due to its clean burning nature. In addition, as LPG is excellent in the minimum hazardous exhaust emissions and better performance, LPG vehicles are being rapidly developed as economical and low pollutant ones. In the present work, LPG is admitted into the Compression Ignition engine in Dual fuel mode. The experiment is carried on a 4 stroke CI engine with Diesel as injected fuel, LPG as inducted fuel. The engine is run under different operating conditions and in each case the optimum flow rates of LPG is determined for best efficiency. At each operating condition, the efficiency, exhaust gas temperature and the emission characteristics are obtained and analyzed. It was found that brake thermal efficiency is maximum at a LPG flow rate of 0.5kg/hr.