R.P. CHOWDARY, M. RAVI CHANDRA AND M.V.S. MURALI KRISHNA
Abstract
The research work on alternative fuels has been the topic of wider interest in the context of depletion of fossil fuels, ever increase of economic burden on developing countries like India and increase of pollution levels with conventional fossil fuels. Alcohols and vegetable oils are suitable substitutes for diesel fuels as they are renewable in nature. However, use of alcohols in internal combustion engines is limited in India, as these fuels are diverted to Petro-Chemical industries and hence much emphasis is given to the non-edible vegetable oils as alternative fuels in Internal Combustion engines. Because of drawbacks of low volatility and high viscosity associated with non-edible vegetable oils, these fuels are converted into biodiesel by the process known as biodiesel, which have less viscous and improved cetane number when compared to crude vegetable oils. However, moderate viscosity of biodiesel call for hot combustion chamber, provided by partially adiabatic diesel engine (PADE). Investigations were carried out on PADE with varied air gap thicknesses and injection pressures with tamarind bio-diesel at normal temperature. The optimum thickness of air gap was found to be 3 mm for reduction of pollutants, in comparison with conventional engine (CE) with test fuels of biodiesel and diesel.