Analysis and Simulation of Air Drag in Vehicles Close-Following

Abstract:

Vehicles drag reductions arising from close spacing are studied and verified by some research institutes. But this solution was queried by an experiment carried in RMIT University in 2006. Based on two standard Ahmed Bodies, Computational Fluid Dynamics(CFD) method is used to study this problem in this paper. The calculation results by comparing four different CFD turbulence models show that the drag coefficient of the rear car is more than the lead car, and even more than the isolated car when the space of these two cars is less than one time of car length. Furthermore, the calculate results of these four turbulence models show that the standard model is the best model to simulate this problem, and different far field condition will influence the calculate results much more. Therefore, the research of this paper verifies that drag reductions from close spacing still need to be studied.

• Periodical: Applied Mechanics and Materials (Volumes 152-154)
• Pages: 1438-1442
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.152-154.1438
• Online since: January 2012
• Authors: Juan Zhang, Zuo Jun Li, Bin Bai, Lei Zhang
• Keywords: Ahmed Body, Computational Fluid Dynamics (CFD), Drag Coefficient, Turbulence Model

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