Investigations on Performance of a Diesel Engine Operated with Raw Cardanol and Kerosene Blends

Abstract

Worldwide diesel engines are the main source of power for heavy duty equipments in mines and other applications. Since the world crude oil reserves are depleting very fast, there is a need for alternative source. The biodiesel originated from animal fats or vegetable oils are the easier alternatives for diesel fuel, which can be utilised without much engine alterations. However, increased cost of the biodiesel due to the esterification process involved in the production of biodiesel is a limiting factor for vast usage of this alternative. In this research work, raw Cardanol extracted from cashew nut shell is tested as a diesel engine fuel without esterification. To reduce the viscosity of Cardanol, it was blended with kerosene. Experiments were carried out in a 3.5 kW four stroke single cylinder diesel engine using different blends of Cardanol and kerosene, such as BK10 (10% kerosene and 90% Cardanol), BK20% (20% kerosene and 80% Cardanol), BK30 (30% kerosene and 70% Cardanol), BK40% (40% kerosene and 60% Cardanol) as a fuel. Performance parameters such as brake thermal efficiency, brake specific fuel consumption, exhaust gas temperature and the exhaust emissions of unburned hydrocarbon, carbon monoxide, oxides of nitrogen and smoke were measured and compared with diesel fuel. Effect of the engine operating parameters like, compression ratio, injection pressure and injection timing on the engine performance are also investigated. Using the taguchi method, the experimental results were optimised and BK30 blend proved as the most favourable blend for optimum engine performance with minimum emissions, under the following operating conditions: compression ratio - 18:1; injection pressure - 220 bar; injection timing - 24.5°BTDC; load - 12 kg. A fuel cost reduction by about 22% could be observed upon using BK30 biofuel blend as a replacement to diesel fuel in mine machineries. Invention of this novel biofuel blend increases the effective utilisation of Cardanol as a biofuel.