A Computational fluid dynamics three-dimensional analysis of a top fuel dragster.

摘要

It is the intent of this study to offer a feasible alternative for the dragster community to model fluid flow, provide insight into the grid generation issues faced with the accurate modeling of a full 3-D model of a dragster, and identify areas of highest drag based on a full 3-D model instead of a simplified or incomplete model. A numerical study of the flow field over a dragster in proximity to the ground is presented to access and improve the aerodynamic performance of a top fuel dragster. A parallel incompressible flow simulation system based on generalized grids is used for the analysis of the flow field around the dragster. The integral form of artificial compressibility formulation of the Navier-Stokes equations is used as the governing equations of the flow field. The flow simulation system is modified to specify the rotating and translating boundaries. The developed flow simulation system is validated with benchmark test cases and the results from the numerical study are presented. A rotating and stationary wheel simulation was completed and compared to experimental data so rotating wheels effects on the flow field could be studied. The aerodynamic force coefficients such as the coefficient of lift CL and the coefficient of drag CD are used as the measure of the aerodynamics performance parameters for the dragster. For the Euler simulation the CL = -1.41 and CD = 0.77. For the Navier Stokes dragster with rotating wheels in turbulent flow the C L = -2.17 and the CD = 1.38. For the Navier Stokes dragster with stationary wheels in turbulent flow the CL = -2.86 and the CD = 1.75. Windtunnel and Computational Fluid Dynamic (CFD) simulations for other sports cars were used for verification since theses were unavailable for the dragster. All cases are within accepted ranges for other sports cars.