Study on Diesel Combustion by Preheated Inlet Air with Blends of Diesel and Biodiesel

The objective of the present study is to save the conventional primary energy resources and to reduce overall exhaust emission of compression ignition (CI) engine simultaneously. To obtain the objective, it was emphasized on finding out a potential non-edible vegetable oil for providing raw material of biodiesel production and to adopt this biodiesel as a suitable alternative of diesel by utilizing engine's exhaust energy. In the present study the biodiesel was prepared in laboratory from non-edible vegetable oil (Neem oil) by transesterification process with methanol, where sodium hydroxide (NaOH) was used as a catalyst. Biodiesel was varied from 5 to 20% for preparing diesel biodiesel blends ranging between B5 to B20 respectively. Laboratory engine's exhaust energy was used to preheat the inlet air passing through a counter flow heat exchanger of inlet air preheating set up. Inlet air temperature was raised by controlling the amount of exhaust gas flowing through air preheating attachment and fixed at 50, 55 and 60°C. The improvement in overall engine performance for a certain degree of inlet air temperature increasing over normal inlet air was shown in this paper. It was found that B20 with preheated inlet air has significant effect on NOx emission reduction in diesel combustion.