Influence Of Injection Timing On Exhaust Emissions Of High Grade Semi Adiabatic Diesel Engine With Preheated Cotton Seed Biodiesel

ABSTRACT Biodiesels derived from vegetable oils present a very promising alternative for diesel fuel, since they have numerous advantages compared to fossil fuels. They are renewable, biodegradable, provide energy security and foreign exchange savings besides addressing environmental concerns and socio–economic issues. However drawbacks associated with biodiesel of high viscosity and low volatilitywhich cause combustionproblems in CI engines, call for engine with hot combustion chamber. They have significant characteristics of higher operating temperature, maximum heat release, and ability to handle lowcalorific value fuel. Investigations were carried out to determine exhaust emissions with low heat rejection combustion chamber with cotton seed biodiesel. It consisted of an air gap insulated piston,an air gap insulated liner and ceramic coated cylinder head with different operating conditions of cotton seed biodieselwith varied injection timing. Engine with LHR combustion chamber with biodiesel showed reduction of particulate emissions at 27obTDCand at optimum injection timingand increased nitrogen oxide levels over CE.