COMBUSTION HEAT RELEASE RATE ANALYSIS OF C.I. ENGINE WITH SECONDARY CO-INJECTION OF DEE-H2O SOLUTION - A VIBRATIONAL APPROACH

This paper discusses the combustion propensity of single cylinder direct injection engine fueled with palm kernel methyl ester (PKME), which is non-edible oil and a secondary co-injection of saturated Diethyl ether (DEE) with water. DEE along with water is fumigated through a high pressure nozzle fitted to the inlet manifold of the engine and the flow rate of the secondary injection was electronically controlled. DEE is known to improve the cold starting problem in engines when used in straight diesel fuel. However, its application in emulsion form is little known. Experimental results show that for 5% DEE-H2O solution injection, occurrence of maximum net heat release rate is delayed due to controlled premixed combustion, which normally helped in better torque conversion when the piston is in accelerated mode. Vibration measurements in the frequency range of 900Hz to 1300Hz revealed that a new mode of combustion has taken place with different excitation frequencies.