Energetic and Exergetic Analyses of a Dual-Fuel Diesel Engine Run on Preheated Intake Biogas-Air Mixture and Oxygenated Pilot Fuels

Abstract

In the present study of energy and exergy, the raw biogas is chosen as the less reactive inducted renewable fuel in dual-fuel mode (DFM). Further, some crucial parameters like global fuel-air equivalence ratio (Φglobal), intake charge preheating, and various liquid oxygenated fuels blended with diesel as the pilot fuel are considered to improve the DFM engine performance. The experiments at part and higher loads are carried out at the engine’s standard compression ratio (CR) and injection timing (IT). The parameters examined are the energy and exergy potential of fuel input, cooling water, exhaust gas, exergy destruction, energy efficiency, exergy efficiency, entropy generation, energy and exergy recovery from the exhaust, and emissions. Energy, exergy and emissions are noticed to be improved significantly at higher loads, with preheating, and with the use of blends of oxygenated pilot fuels at optimum Φglobal. The superior results are found with the ternary blends of diethyl ether (TB-DEE) as the pilot fuel. At higher load of 21.78 N·m with TB-DEE blend (pilot fuel), the maximum energy recovery, exergy recovery, reductions of CO and Unburnt hydrocarbon (HC) of 26.99%, 36.03%, 51.72%, and 67.39%, respectively, are estimated in comparison with the case without preheating.