Preliminary Investigation of Diesel Engine with Additional Injection of Ethyl Alcohol

The objective of the work was investigation of possibility of dual fuelling of CI engine with diesel fuel and ethyl alcohol in order to decrease engine emission and increase its thermal efficiency. Alcohol, which is injected to the engine inlet port evaporates quickly, but doesn't ignite (due to low cetane number). After self-ignition of diesel fuel, ignited alcohol would promote further burning of it, that results in shorter combustion period, and thanks to that increasing of thermal efficiency of the engine. Furthermore, later injection of diesel fuel would result in increasing of indicated work and decreasing of NOx. Preliminary investigation, which was carried out with the use of 1HC102 CI engine with modified inlet duct for injection of ethyl alcohol, showed that at the same torque and speed: • thermal efficiency increased, • engine torque increased, • emission of HC and soot decreased, • emission of greenhouse gas (CO2) decreased, • emission of NOx increased (beginning of diesel fuel injection was set up by the producer). Pressure histories measured during investigation were the base for computation of parameters which describe combustion process. For calculation were utilised computer programmes worked out in Department of IC Engines and Automobiles of Technical University of Radom. The results showed that there is influence if injected ethyl alcohol on engine operation, particularly it was noticed that the rate of fuel burning and heat release were higher.