Economics, combustion and performance assessment of a biodiesel engine

Abstract

Today s world facing problem of increasing environmental pollution, growing threat of depleting fossil fuels, and ever increasing uncertainty of fuel prices. Indiscriminate extraction and lavish consumption of fossil fuels have led to reduction in underground based carbon resources. This situation offers us a challenge as well as an opportunity to look for substitutes of fossil fuels for both economic and environmental benefits to the country; thus, there is urgent need to explore environment friendly, cost effective, renewable energy sources which can full fill the future energy needs. Among the various renewable energy choices, vegetable oils and biodiesel from seed oil crops have a potential for meeting the increasing requirements of petroleum and its products. A lot of work has been done on utilization and optimization of several vegetable oils and biodiesels as an alternative fuel for compression ignition engines including edible oils. However, there are plenty of oilseeds which remain unutilized or underutilized for biodiesel production. Thumba oil is one of the underutilized or unexploited non-edible vegetable oil, available in large quantities in Rajasthan and its potential suitability for biodiesel production for diesel engine fuel is still not evaluated comprehensively. In the present study, extensive experimental investigations have been carried out to assess the potential suitability and practical viability of thumba oil and thumba biodiesel as diesel engine fuel in a single cylinder, direct injection, four-stroke, water-cooled, naturally aspirated variable compression ratio multi-fuel diesel engine. The optimization of engine operation with diesel fuel, thumba oil, thumba biodiesel and their different blends in diesel was also conducted. The engine selected for this study was typical of the ones widely used in agricultural, rural and industrial sector in India.