CFD Simulation of a Simplified Automotive Model for Various Rear Slant Angle

Abstract:

In the early design phase of automotive sector, the flow field around the vehicle is important in decision making on design changes. It would consume a lot of money and time for multiple prototypes development if adopt traditional testing method which is wind tunnel test. Thus, CFD Simulation plays an important role here. In this paper, a CFD simulation study was conducted on a simplified automotive model called Davis model with constant velocity of 40 m/s. Modification of rear slant angle bring significant effects on the wakes produced which also affect the drag performance. Many configurations of body designs can be produced by a single rear slant angle. So that, fixed rear slope and fixed rear height configuration have been chosen for investigations for various rear slant angles. In this paper, the flow of Davis model especially on the rear slanted surface is discussed. Pressure coefficient contour, pressure coefficient plot and vorticity structures are presented. This work shows that the drag coefficient value vary between fixed rear slope model and fixed rear height model even for the same rear slant angle under a range of yaw angle.

• Periodical: Applied Mechanics and Materials (Volume 660)
• Pages: 724-729
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.660.724
• Online since: October 2014
• Authors: S. Mansor, N.A.R. Nik Mohd, C.W. Chung*
• Keywords: CFD Simulation, Davis Model, Vehicle Aerodynamics

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