Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-19T05:22:16.577Z Has data issue: false hasContentIssue false
  • English
  • Français

Vortical Flow Structure in the Wake of an Estate Car

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

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: [email protected] (P. G.-Y. Huang), [email protected] (T. W.-H. Sheu)
Get access

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 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1]Himeno, R., Car aerodynamic simulation on NEC SX-4 at Nissan research center, SX world online magazine No. 18, spring 1996.Google Scholar
[2]Kleber, A., Simulation of airflow around an Opel Astra vehicle with Fluent, JA132, Fluent Inc., 2001.Google Scholar
[3]Kapadia, S., Roy, S., and Wurtzler, K., Detached eddy simulation over a reference Ahmed car model, AIAA-2003-0857, 2003.Google Scholar
[4]Pro/ENGINEER Wildfire, Parametric Technology Corporation, 2010.Google Scholar
[5]ICEM-CFD, ANSYS Inc., 2010.Google Scholar
[6]CFX, ANSYS Inc., 2010.Google Scholar
[7]FIELDVIEW, Intelligent Light, 2010.Google Scholar
[8]Launder, B. E., Reece, G. J., and Rodi, W., Progress in the developments of a Reynolds-stress turbulence closure, J. Fluid Mechanics, Vol. 68, pp. 537–566, 1975.Google Scholar
[9]Clarke, D. S. and Wilkes, N. S., The calculation of turbulent flows in complex geometries using a differential stress model, AERE-R, Vol. 13428, 1989.Google Scholar
[10]Makowski, Francis T. and Kim, S. E., Advancesin external-aero simulation of ground vehicles using the steady RANS equations, SAE Paper, 2000-01-0484, 2000.CrossRefGoogle Scholar
[11]Rhie, C. M. and Chow, W. L., Numerical study of the turbulent flow past an airfoil with trailing edge separation, AIAA J1, 21, pp. 1527–1532, 1983.Google Scholar
[12]Pantankar, S. V., Numerical Heat Transfer and Fluid Flow, Hemishere Publishing co., 1983.Google Scholar
[13]Anderson, D. A. and Tannehill, J. C. and Pletcher, R. H., Computational Fluid Mechanics and Heat Transfer, Hemishere Publishing co., 1984.Google Scholar
[14]Hutchinson, B. R. and Raithby, G. D., A multigrid method based on the additive correction strategy, Numerical Heat Transfer, Vol. 9, pp. 511–537, 1986.CrossRefGoogle Scholar
[15]Nouzawa, T., Haruna, S., Hiasa, K. and Nakamura, T., Analysis of wake pattern for Reducing aerodynamic drag of notchback model, SAE paper, 900318, 1990.Google Scholar
[16]Himeno, R., Takagi, M., Fujitani, K. and Tanaka, H., Numerical analysis of the airflow around automobile using multi-block structured grid, SAE paper, 900319, 1990.Google Scholar
[17]Guckenheimer, J. and Holmes, P., Nonlinear oscillations, dynamical systems, and bifurcations of vector fields, 3rd ed., New York: Springer-Verlag, pp. 149–150, 1997.Google Scholar
[18]Sau, A. A. and Hwang, Robert R. and Sheu, Tony W. H. and Yang, W. C., Unsteady interaction of trailing vortices in the wake of a wall-mounted rectangular block, Physical Review E, 68, 056303, 2003.Google Scholar
[19]Sujuki, D. and Haimes, R., Identification of swirling flow in 3-D vector fields, AIAA 95-1715, 1995.Google Scholar
[20]Haimes, R. and Kenwright, D., On the velocity gradient tensor and fluid feature extraction, AIAA 99-3288, 1999.Google Scholar