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Vortical Flow Structure in the Wake of an Estate Car

Part of: Partial differential equations, initial value and time-dependent initial-boundary value problems Incompressible viscous fluids

Published online by Cambridge University Press:  15 October 2015

Phillip Gwo-Yan Huang  and
Tony Wen-Hann Sheu
Phillip Gwo-Yan Huang
Affiliation:
Hon Hai Precision Ind. Co., Ltd., Taipei, Taiwan
Tony Wen-Hann Sheu*
Affiliation:
Department of Engineering Science and Ocean Engineering, National Taiwan University, Taipei, Taiwan
*
*Corresponding author. Email addresses: gwoyanhuang@gmail.com (P. G.-Y. Huang), twhsheu@ntu.edu.tw (T. W.-H. Sheu)
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Abstract

A finite volume simulation of unsteady vortical wake flow behind a square-back estate car is presented. The three-dimensional time-averaged incompressible Navier-Stokes equations are solved together with the Reynolds stress transport equations for turbulence. By virtue of the simulated surface streamlines, the physics of fluid can be extracted using the topological theory. In addition, the simulated topological singular points and lines of separation are plotted on the car surface. The vortical flow motions that developed behind the mirrors, wheels and car body are explored by means of the simulated time evolving vortex corelines. The formation and interaction of the vortex systems in the wake are examined by tracing the instantaneous streamlines in the vicinity of the simulated vortex corelines. The vortex street behind the estate car is also illustrated by the simulated streaklines. Finally the Hopf bifurcation phenomenon is revealed by the time-varying aerodynamic forces on the car.

Keywords

Vortical wake flowestate cartopological theoryvortex corelinesvortex streettime-varying aerodynamic forces

MSC classification

Secondary: 65M08: Finite volume methods 76D05: Navier-Stokes equations
Type
Research Article
Information
Communications in Computational Physics , Volume 18 , Issue 4 , October 2015 , pp. 881 - 900
Copyright
Copyright © Global-Science Press 2015 

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