Computational Simulation of Cross-Wind Sensitivity of an External Body

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
© 2015 by IJETT Journal
Volume-30 Number-9
Year of Publication : 2015
Authors : Shishir Sirohi, Yagnavalkya Mukkamala
DOI :  10.14445/22315381/IJETT-V30P281


Shishir Sirohi, Yagnavalkya Mukkamala"Computational Simulation of Cross-Wind Sensitivity of an External Body", International Journal of Engineering Trends and Technology (IJETT), V30(9),433-439 December 2015. ISSN:2231-5381. published by seventh sense research group

The main objective of this paper is to elucidate the variation of various aerodynamic factors (drag lift) and also examine pressure variations when a body corners. This is accomplished by investigating the variation of the rear slant angle of the Ahmed body and its effect on the drag and lift coefficients through numerical simulation .To study variations in a cornering or an overtaking scenario, yaw angle is introduced in the body. The simplified vehicle geometry: Ahmed Reference Model has been used as a benchmark. Three types of slant angle categories have been chosen for the present study notch back, hatch back, square back and a comparison study has been carried out. The computational part consists of numerical simulation of the flow around the Ahmed Body employing CFD (Computational Fluid Dynamics) techniques. In numerical simulation results, pressure-based solver was utilized and the turbulence model employed was k-Epsilon realizable model with non-equilibrium wall function for near wall treatment. The designing of model used in this paper is done through the SOLIDWORKS ‘14; and CFD simulation carried out in FLUENT (ANSYS 15).


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Cross-wind Simulation, Ahmed body, k-Epsilon realizable model, Drag, Lift, Pressure, Cl, Cd.