Steady-state Reynolds averaged Navier–Stokes (RANS) simulations are presented for the three-dimensional flow over a generic tractor trailer placed in the Auburn University 3×4ft2 suction wind tunnel. The width of the truck geometry is 10 in., and the height and length of the trailer are 1.392 and 3.4 times the width, respectively. The computational model of the wind tunnel is validated by comparing the numerical results with the data from the empty wind tunnel experiments. The comparisons include the boundary layer properties at three different locations on the floor of the test section and the flow angularity at the beginning of the test section. Three grid levels are used for the simulation of the truck geometry placed in the test section of the wind tunnel. The coarse mesh consists of 3.4×106 cells, the medium mesh consists of 11.2×106 cells and the fine mesh consists of 25.8×106 cells. The turbulence models used for both the empty tunnel simulations and the truck geometry placed in the wind tunnel are the standard Wilcox 1998 k-ω model, the SST k-ω model, the standard k-ε model, and the Spalart–Allmaras model. The surface pressure distributions on the truck geometry and the overall drag are predicted from the simulations and compared with the experimental data. The computational predictions compared well with the experimental data. This study contributes a new validation data set and computations for high Reynolds number bluff-body flows. The validation data set can be used for initial assessment in evaluating RANS models, which will be used for studying the drag or drag trends predicted by the baseline truck geometries.

1.
2003, US DOE Transportation Energy Data Book: Edition z23, http://www-cta.ornl.gov/data/http://www-cta.ornl.gov/data/.
2.
McCallen
,
R. C.
,
Salari
,
K.
,
Ortega
,
J. M.
,
DeChant
,
L. J.
,
Hassan
,
B.
,
Roy
,
C. J.
,
Pointer
,
W. D.
,
Browand
,
F.
,
Hammache
,
M.
,
Hsu
,
T. -Y.
,
Leonard
,
A.
,
Rubel
,
M.
,
Chatalain
,
P.
,
Englar
,
R.
,
Ross
,
J.
,
Satran
,
D.
,
Heineck
,
J. T.
,
Walker
,
S.
,
Yaste
,
D.
, and
Storms
,
B.
, 2004, “
DOE’s Effort to Reduce Truck Aerodynamic Drag—Joint Experiments and Computations Lead to Smart Design
,” AIAA Paper No. 2004-2249.
3.
Cooper
,
K. R.
, 2003, “
Truck Aerodynamics Reborn—Lessons From the Past
,” SAE Paper 2003-01-3376.
4.
Storms
,
B. L.
,
Ross
,
J. C.
,
Heineck
,
J. T.
,
Walker
,
S. M.
,
Driver
,
D. M.
, and
Zilliac
,
G. G.
, 2001, “
An Experimental Study of the Ground Transportation System (GTS) Model in the NASA Ames 7- by 10-ft Wind Tunnel
,”
NASA
, Report No. TM-2001-209621.
5.
Storms
,
B.
,
Satran
,
D.
,
Heineck
,
J.
, and
Walker
,
S.
, 2004, “
A Study of Reynolds Number Effects and Drag-Reduction Concepts on a Generic Tractor-Trailer
,” AIAA Paper No. 2004-2251.
6.
Roy
,
C. J.
,
Payne
,
J. L.
, and
McWherter-Payne
,
M. A.
, 2006, “
RANS Simulations of a Simplified Tractor/Trailer Geometry
,”
ASME J. Fluids Eng.
0098-2202,
128
, pp.
1083
1089
.
7.
Salari
,
K.
,
Ortega
,
J. M.
, and
Castellucci
,
P. J.
, 2004, “
Computational Prediction of Aerodynamic Forces for a Simplified Integrated Tractor-Trailer Geometry
,” AIAA Paper No. 2004-2253.
8.
Pointer
,
W.
, 2004, “
Evaluation of Commercial CFD Code Capabilities for Prediction of Heavy Vehicle Drag Coefficients
,” AIAA Paper No. 2004-2254.
9.
Roy
,
C. J.
,
Brown
,
J. C.
,
DeChant
,
L. J.
, and
Barone
,
M. A.
, 2004, “
Unsteady Turbulent Flow Simulations of the Base of a Generic Tractor/Trailer
,” AIAA Paper No. 2004-2255.
10.
Unaune
,
S. V.
,
Sovani
,
S. D.
, and
Kim
,
S. E.
, 2005, “
Aerodynamics of a Generic Ground Transportation System: Detached Eddy Simulation
,” SAE Paper No. 2005-01-0548.
11.
Doyle
,
J. B.
,
Hartfield
,
R. J.
, and
Roy
,
C. J.
, 2006, “
Tractor Trailer Optimization by a Genetic Algorithm With CFD
,” AIAA Paper No. 2006-3863.
12.
Hammache
,
M.
, and
Browand
,
F.
, 2004, “
On the Aerodynamics of Tractor-Trailers
,”
The Aerodynamics of Heavy Vehicles: Trucks, Buses and Trains (Lecture Notes in Applied and Computational Mechanics)
,
R. C.
McCallen
,
F.
Browand
, and
J. C.
Ross
, eds.,
Springer-Verlag
,
Heidelberg
, Vol.
19
.
13.
Pointwise Inc.
, GRIDGEN v.15, User Manual.
14.
Roy
,
C. J.
, 2005, “
Review of Code and Solution Verification Procedures in Computational Simulation
,”
J. Comput. Phys.
0021-9991,
205
(
1
), pp.
131
156
.
15.
Salas
,
M. D.
, 2006, “
Some Observations on Grid Convergence
,”
Comput. Fluids
0045-7930,
35
, pp.
688
692
.
16.
Fluent Inc.
, 2003, FLUENT 6.1 User’s Guide.
17.
Wilcox
,
D. C.
, 1998,
Turbulence Modeling for CFD
,
2nd ed.
,
DCW Industries, Inc.
,
La Canada, CA
.
18.
Roy
,
C. J.
, and
Blottner
,
F. G.
, 2003, “
Methodology for Turbulence Model Validation: Application to Hypersonic Flows
,”
J. Spacecr. Rockets
0022-4650,
40
(
3
), pp.
313
325
.
19.
Veluri
,
S. P.
,
Roy
,
C. J.
,
Ahmed
,
A.
, and
Rifki
,
R.
, 2006, “
Preliminary RANS Simulations and Experimental Study of a Tractor/Trailer Geometry
,” AIAA Paper No. 2006-3857.
20.
Roache
,
P. J.
, 1994, “
Perspective: A Method for Uniform Reporting of Grid Refinement Studies
,”
ASME J. Fluids Eng.
0098-2202,
116
, pp.
405
413
.
21.
Roache
,
P. J.
, 1998,
Verification and Validation in Computational Science and Engineering
,
Hermosa
,
New Mexico
.
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