Investigation of the Kinematic Viscosity of Cottonseed, Palm, Soybean and Jatropha Biodiesel with Diesel Fuel

Biodiesel is a biodegradable and non-toxic alternative fuel produced from various feedstocks of vegetable oil and animal fats and used as an alternative fuel in the transportation sector such as automotive, marine and small aircraft. The higher viscosity of biodiesel causes serious problems when it is used in the conventional engine without modification. Considering this problem the study has been carried out towards two objectives. The first objective is to identify the different feedstock of biodiesel and to study the variation of kinematic viscosity as a function of temperature and blend ratio with diesel fuel. The second objective is to correlate and develop the mathematical model of variation of kinematic viscosity as a function of temperature and blend ratio with diesel fuel by using non–linear regression analysis. Test fuels used were a conventional diesel, neat biodiesel of Cottonseed, Palm, Soybean and Jatropha oil, and their blends with blending ratio of 20, 40, 60 and 80% with diesel fuel. The blends were prepared on the volume basis and viscosities were measured as per IS: 1448 [P: 25]-1976 test methods. Equation given by Arrhenius and studied by Grunberg and Nissan was used to predict the viscosities of the biodiesel blends. For all blends of Cottonseed, Palm, Soybean and Jatropha oil biodiesel, it is reported that, there is an excellent agreement between the measured and predicted values of the viscosities and have an absolute maximum error up to 0.001. The viscosities of the test fuels were found to decrease linearly with increasing temperature and decreasing blend ratio.