Performance Evaluation and Wear Analysis of a Compression Ignition Engine Operating with Straight Vegetable Oil and Diesel Blend

Now-a-days uses of alternative fuels in internal combustion engines are essential due to limited reserve and harmful combustion effects of fossil fuels. The various alternative fuels upon which research works are going on are CNG, LPG, biodiesel, hydrogen etc. Among these, biodiesel plays an important role for diesel engines. Literature review reveals that in some cases even 50% biodiesel can be used in diesel engines where satisfactory performance and emission results have been obtained. Biodiesel is produced from vegetable oils like Neem, Karanja, Jatropha, Castor, Mahua etc. through transesterification process which makes vegetable oil less viscous. But transesterification process requires some money, man and machine. So instead of using higher proportion of biodiesel with mineral diesel, we can significantly use lower percentage of straight vegetable oils with conventional diesel to make them use in engines. With a view to investigate on straight vegetable oil without making them biodiesel through transesterification process, neem vegetable oil is taken in this present study. Various blends of diesel and neem have been prepared like N30 fuel has been prepared in which 30% straight neem vegetable oil is mixed with 70% mineral diesel by volume. Now a single cylinder, four strokes, constant compression ratio, water cooled, vertical diesel engine is run by these fuel blends as well as by neat diesel. Various physical, chemical and thermal properties have been studied by using standard apparatus. Performance and emission results have been taken and compared with those of using mineral diesel. Wear has negative effects on the operating of engine parts. Wear rate determination are taken into account with a view to develop a maintenance programme. For measurement of wear rate, Ferrographic technique (both quantitative and qualitative) has been used. Lubricating oil from crank has been collected after 5, 10, 15 and 20 h. Wear particle concentration (WPC) have been studied and images are taken using Ferro scope. Results show that wear rate is marginal. Now we need to check wear results for long duration running of the engine. Therefore, considering all aspects i.e. performance, emission and wear rate we can use small portions of vegetable oil with mineral diesel for short duration.