Journal of Jilin University(Engineering and Technology Edition) ›› 2019, Vol. 49 ›› Issue (4): 1034-1042.doi: 10.13229/j.cnki.jdxbgxb20180369

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Investigation of vortical structures in wake of Ahmed body by delayed detached⁃eddy simulation turbulence model using immersed boundary method

Xin CHEN(),Ming LI,Xin⁃jian RUAN,Ning WANG,Jia⁃ning WANG   

  1. State Key Laboratory of Automotive Simulation and Control, Jilin University, Changchun 130022, China
  • Received:2018-04-18 Online:2019-07-01 Published:2019-07-16

Abstract:

A new solver is implemented based on immersed boundary method (IBM) and pressure implicit with splitting of operators (PISO) algorithm. By this IBM-PISO solver, the external flow of Ahmed body is simulated using the delayed detached-eddy (DDES) turbulence model. First, the time-averaged features and shedding frequency of 2D cylinder cases are used for the verification of the IBM module and IBM-PISO solver. Then the instantaneous flow field, time-averaged features, and vortical flow structures of Ahmed body are investigated. The effect of slant angle and the transport of vortical structures are compared. The results show that the IBM-PISO solver produces accurate results at separation zone and main vortical flow structures including recirculation vortices, horse-shoe vortices at the upper surface and at the foot of the front surface, C-pillar vortices, and lateral vortices. The transport in the wake enhances the turbulence of C-pillar vortices and renders their domination over the far-wake flow field. The effect of slant angle is based on controlling the flow separation at the slant and confined to the near-wake region.

Key words: vehicle engineering, immersed boundary method(IBM), delayed detached?eddy simulation (DDES) turbulence model, Ahmed body, vortical structures

CLC Number: 

  • U461.1

Fig.1

Time?averaged flow structure of cylinder at ReD = 30"

Table 1

Comparison of wake parameters at ReD =30"

L/D Lx/D Ly/D φ/(°)
当前算例 1.56 0.53 0.52 48.00
实验[13] 1.55 0.54 0.54 50.00
IBM仿真[14] 1.70 0.56 0.52 48.05

Fig.2

Instantaneous streamline pattern and vorticity contour in wake of cylinder at ReD = 185"

Fig.3

Ahmed vehicle model"

Fig.4

Computational domain for external flow field of Ahmed vehicle model"

Fig.5

Profiles for streamwise component of velocity(θ = 25°)"

Fig.6

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Fig.7

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Fig.8

Streamline patterns in YZ plane at rear of Ahmed body (θ = 25°)"

Fig.9

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Fig.10

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Fig.11

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Fig.12

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Fig.13

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Fig.14

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1 Mittal R , Iaccarino G . Immersed boundary methods[J]. Annual Review of Fluid Mechanics, 2005, 37(1):239⁃261.
2 Tseng Y H , Ferziger J H . A Ghost⁃cell Immersed Boundary Method for Flow in Complex Geometry[M]. New York: Academic Press Professional, 2003.
3 Tay W B , Deng S , Oudheusden B W V , et al . Validation of immersed boundary method for the numerical simulation of flapping wing flight[J]. Computers and Fluids, 2015, 115: 226⁃242.
4 Bruneau C H , Khadra K , Mortazavi I , et al . Flow analysis of square⁃back simplified vehicles in platoon[J]. International Journal of Heat and Fluid Flow,2017,66: 43⁃59.
5 Grandemange M , Cadot O , Courbois A , et al . A study of wake effects on the drag of Ahmed׳s squareback model at the industrial scale[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2015, 145: 282⁃291.
6 Wang H , Zhou Y , Zou C , et al . Aerodynamic drag reduction of an Ahmed body based on deflectors[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2016, 148:34⁃44.
7 Keogh J , Barber T , Diasinos S , et al . The aerodynamic effects on a cornering Ahmed body[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2016, 154: 34⁃46.
8 Tunay T , Yaniktepe B , Sahin B . Computational and experimental investigations of the vortical flow structures in the near wake region downstream of the Ahmed vehicle model[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2016, 159: 48⁃64.
9 Venning J , Jacono D L , Burton D , et al . The effect of aspect ratio on the wake of the Ahmed body[J]. Experiments in Fluids, 2015, 56(6): 126.
10 Guilmineau E , Deng G B , Queutey P , et al . Assessment of hybrid LES formulations for flow simulation around the Ahmed body[J]. Turbulence and Interactions (TI 2015)Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 2015, 135: 171⁃176.
11 Spalart P R , Allmaras S R . A one⁃equation turbulence model for aerodynamic flows[J]. Recherche Aerospatiale, 1994(1): 5⁃21.
12 Spalart P R , Jou W H , Strelets M , et al . Comments on the feasibility of LES for wings, and on a hybrid RANS/LES approach[C]∥The 1st Air Force Office of Scientific Research International Conference on DNS, 1997.
13 Coutanceau M , Bouard R . Experimental determination of the main features of the viscous flow in the wake of a circular cylinder in uniform translation. part 1. steady flow[J]. Journal of Fluid Mechanics, 1977, 79(2): 231⁃256.
14 Pinelli A , Naqavi I Z , Piomelli U , et al . Immersed⁃boundary methods for general finite⁃difference and finite⁃volume Navier–Stokes solvers[J]. Journal of Computational Physics, 2010, 229(24): 9073⁃9091.
15 Tritton D J . Experiments on the flow past a circular cylinder at low Reynolds numbers[J]. Journal of Fluid Mechanics, 1959, 6(4): 547⁃567.
16 Williamson C H K . Defining a universal and continuous Strouhal–Reynolds number relationship for the laminar vortex shedding of a circular cylinder[J]. Physics of Fluids, 1998, 31(10): 2742⁃2744.
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