Homogeneity analysis of B30 mixing results with additives in mixing tanks using computational fluid dynamics (CFD)

B30 has been implemented in Indonesia as a commercial fuel. The specification of B30 could decrease if B30 is stored for a few months or more. The use of additives in B30 fuel can be conducted to increase B30 quality and to make the specification of B30 more stable. However, the mixture of B30 and additive needs to be homogenous. This study aims to analysis the homogeneity of B30 and additive mixture according to the density and fraction volume. CFD is used to simulate the mixing process of B30 and additive. CFD simulation uses angular velocity and resident time as main parameter, while the dimension of mixing tank uses the design of existing mixing tank. Compared to other impeller speed used, the result shows that at 900 rpm impeller speed is the fastest mixing time in achieving homogeneity of mixing B30 with additives and produces a more equal fluid flow velocity at all levels of the tank. The mixture can reach homogeneity of volume fraction at 15 s and mixture density at 20 s. According to the homogeneity parameters, the volume fraction and density values obtained from the CFD simulation (860 kg/m3) is not significantly different from the density obtained from the laboratory test measurement (858.7 kg/m3), that validate the CFD simulation model to represent the mixing of B30 and additive.