Investigating the effects of biofuel on the performance, exhaust emissions and combustion characteristics in a diesel engine power generator

In this study, biofuel was produced soya oil by the method of re-esterification (transesterification) and this biofuel and reference diesel fuels (DF) were blended for the experiment tests. This blends, volumetrically is 5% biofuel + 95% diesel fuel (SYB5), 10% biofuel + 90% diesel fuel (SYB10), 20% biofuel + 80% diesel fuel (SYB20) and 50% biofuel + 50% diesel fuel (SYB50). Before engine testing, the physical and chemical properties of all test fuels were determined. Then, respectively DY, SYB5, SYB10, SYB20 and SYB50 fuels were tested at constant engine speed of 1500 rpm and fixed load 3.6 kW, 7.2 kW and 10.8 kW in a diesel engine power generator which have 4 strokes, 4 cylinders, direct injection and water cooling system. When alternative fuels compared to reference diesel fuel combustions graphs of the cylinder internal gas pressure, the heat release rate, the cumulative heat release, the average gas temperature, the mass combustion rate and the knock intensity it has been determined that the curves are parallel to each other and increased engine load for all test fuels increases graphs observed. In addition, specific fuel consumption and NOx emissions are increased at all load values, and effective efficiency and CO emissions are reduced. Unburned HC has been found to increase in part due to the increase in engine load and has been released to more circles in alternative fuels at all loads. Unburned HC has been slightly increased for all test fuels due to increased engine load and has been released more emission to the environment at all loads only in biofuels.