Computational simulation of fuel tank sloshing for a FSAE car using CFD techniques

Abstract

Sloshing refers to the highly random motion of any fluid inside an object where the dynamic forces of the liquid can interact with the object to alter the overall system dynamics. This work summarises the process of designing and simulating the 3-D geometry of a fuel tank using CFD and the volume of fluid (VOF) method considering multi-phase fluid flow predicting fuel slosh movement at a specific capacity within a definite fixed volume.[13-16] As the performance of the engine heavily depends on a constant supply of fuel, the splashing of gasoline inside the partially filled fuel tank can severely affect the performance when subjected to sudden left and right turns during a Slalom in FSAE tracks. This scenario can be modelled, analysed and effectively controlled by reducing pressure intensities inside the tank walls using a set of strategically placed Baffles. Therefore, this study attempts to reduce the sloshing behaviour by considering multiple types of geometries and shows the final geometry chosen using computational simulations inside the fuel tank considering 1.5 litres of fuel and remaining with air inside a 7.3 litres fuel tank, thus predicting the effect of sloshing forces and moments inside the tank structure considering lateral and longitudinal acceleration fields. The model is discussed and results are presented. In addition, this paper can be referred to as a detailed tutorial on how to simulate and take in consideration of all the factors which will be useful in deciding vehicle fuel requirements and optimum design.