EXPERIMENTAL INVESTIGATIONS ON INJECTION TIMING VARIATION AT AN INJECTOR OPENING PRESSURE OF 190BAR ON SEMI- ADIABATIC DIESEL ENGINE WITH EXHAUST GAS RECIRCULATION

Particulate emissions and Nitrogen oxides (NOx) levels are exhaust emissions from compression ignition (CI) engine. Once they are in-haled- in, they cause health hazards, besides environmental impact. Hence control of these emissions are important and an urgent task. In the context of depletion of fossil fuels, coupled with exponential growth rate of traction power engines in automobiles and for human luxuries, energy consumption has increased by many folds. This has triggered ever increase of fuel prices in international market and due to uneven distribution of oil resources in the world, a few oil rich countries are getting benefitted and oil lacking countries are suffering from non- affordability. Alcohols and vegetable oils are important substitutes for diesel fuel, as they are renewable. However, drawbacks associated with vegetable oils (high viscosity and low volatility) and alcohols (low cetane number and calorific value of the alcohols) call for low heat rejection (LHR) diesel engine. Exhaust gas recirculation (EGR) is one of the techniques to reduce pollution levels. Investigations were carried out to determine exhaust emissions of particulate matter and oxides of nitrogen with neat diesel operation at different values of brake mean effective pressure of the engine with varied injection timing with provision of EGR and compared the data with conventional engine with neat diesel operation. LHR engine consisted of air gap insulated piston with Stainless Steel crown, a low thermal conductivity material and air gap insulated liner with Stainless Steel insert. Particulate matter and NOx emissions will reduce with optimum EGR system.