INVESTIGATING THE EFFECTS OF BIODIESEL FROM WASTE COOKING OIL AND ENGINE OPERATING CONDITIONS ON THE DIESEL ENGINE PERFORMANCE BY RESPONSE SURFACE METHODOLOGY

In this research, the application of response surface methodology (RSM) was highlighted to investigate the effects of biodiesel (from waste cooking oil) in fuel mixture (biodiesel and diesel fuel No.2) and engine operating parameters on performance characteristics (brake power, brake torque and BSFC) of a diesel engine. The experiments were conducted on a four cylinder direct-injection diesel engine based on three-factor five-level central composite rotatable design. The developed mathematical models were helpful to predict the response parameters, and further, to identify the significant interactions between the input factors on the responses. Results showed that the use of biodiesel reduces brake power and brake torque up to 18% and 17% respectively. On the other hand, BSFC increases 18 to 24% by using net biodiesel. Also, results showed that an increase in engine load appeared to cause an increase in the brake power and torque up to 68 and 69% respectively. On the other hand, BSFC is higher at low engine load and increases up to 15% by reducing the engine load.