Determination of the density and the viscosities of biodiesel–diesel fuel blends

Abstract

a b s t r a c tIn this study, commercially available two different diesel fuels were blended with the biodiesels produced from six different vegetable oils (sunflower, canola, soybean, cottonseed, corn oils and waste palm oil). The blends (B2, B5, B10, B20, B50 and B75) were prepared on a volume basis. The key fuel properties such as density and viscosities of the blends were measured by following ASTM test methods. Generalized equations for predicting the density and viscosities for the blends were given and a mixing equation, originally proposed by Arrhenius and described by Grunberg and Nissan, was used to predict the viscosities of the blends. For all blends, it was found that there is an excellent agreement between the measured and estimated values of the density and viscosities. According to the results, the density and viscosities of the blends increased with the increase of biodiesel concentration in the fuel blend.

Prediction models for density and viscosity of biodiesel and their effects on fuel supply system in CI engines

“…[5] carried out experimental tests on different biodiesels made of soybean oil, waste palm oil, sunflower oil, corn oil, canola oil, and cottonseed. They suggested a 1 st degree empirical equation, which can relate the density of a biodiesel blend with the percentage of a biodiesel used as shown in equation (3).…”

“…This ratio increases especially when the temperature is below 25 o C [11]. Blending of the biodiesel with diesel and preheating of the biodiesel improves the viscous characteristics significantly [5,12,13]. The viscosity of biodiesel can be estimated from well known mixing laws such as the Grun-Nissan and Katti-Chaudhri laws, which were originally proposed by Arrhenis [14].…”

“…These parameters affect the physical and chemical properties, which also have direct relationship with performance and emission of the engine [4]. Among the biodiesel properties kinematics viscosity, density and heating value are the most important parameters that affect the engine performance and the emission characteristics [5]. One of the major shortcomings of the biodiesels when used in a diesel engine is the detrimental effects caused by the high viscosity of fuel.…”

“…In addition, the higher viscosity of biodiesel fuel affects the start of injection, injection pressure and the fuel spray characteristics, which are the main parameters that affect engine performance and exhaust emission [7,8,9].The density of the diesel fuel is also very important parameter, since other crucial performance parameters of engine such as cetane number and heating value have been correlated against it [10]. In addition, the density values have also been used to measure the amount fuel in fuel system by volumetric method [5]. The variation of the density affects the power and the fuel spray characteristics during fuel injection and combustion in cylinder.…”

“…The effect of mixing on density and viscosity variation of biodiesel with respect to temperature, percentage of blend, and the chemical structure (fatty acid, position and number of double bond) have been well reported. Different empirical correlations have been developed, which relate various performance parameters with density and viscosity of biodiesel [5][6][7][8][9][10][11]. The works of previous researchers on biodiesel density and viscosity have been summarized below.…”