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High-order detached-eddy simulation of external aerodynamics over an SAE notchback model

Published online by Cambridge University Press:  24 July 2017

A. Islam  and
B. Thornber
A. Islam*
Affiliation:
School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney Darlington, NSW 2006, Australia
B. Thornber
Affiliation:
School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney Darlington, NSW 2006, Australia
*
asiful.islam@sydney.edu.au
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Abstract

This research explores the modification and implementation of a Detached-Eddy Simulation (DES) in a high-order compressible solver and its application to automotive aerodynamics. This was conducted on a 20° SAE Reference Notchback Model with a Reynolds number of 2.23 × 105. This DES algorithm implemented within FLAMENCO, which is finite-volume research code operating over multi-block meshes, was used for all the simulations. The primary objectives were to capture unsteady flow features, separated coherent structures and also relax the meshing requirements to improve accessibility to turbulence-resolving methods for realistic configurations. This also aims to better understand the separated flow physics, especially around the base surfaces of the car. Simulations for three mesh refinement levels were compared to wind-tunnel measurements. Even on relatively coarse meshes (~7 m cells) for DES, time-averaged Cp was obtained with maximum errors of <8%.

Type
Research Article
Information
The Aeronautical Journal , Volume 121 , Issue 1243 , September 2017 , pp. 1342 - 1367
Copyright
Copyright © Royal Aeronautical Society 2017 

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Footnotes

This is an adaptation of a paper first presented at the 2015 Asia-Pacific International Symposium on Aerospace Technology in Cairns, Australia

References

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