Heat Transfer Research, no.3, pp.10-20, 2021 (SCI-Expanded)
The drag forces drag coefficient of a typical pickup truck is
investigated experimentally and 3-D numerical analysis is performed. A
detailed 1/4 scaled model is constructed and experiments are performed
at Reynolds numbers around 2x106 in the ANKARA WIND TUNNEL (ART). The
experimental study is divided into two; in the first stage the pressure
distribution along the symmetry axis is measured and in the second stage
the drag forces and overall drag coefficient are measured for five
different wind speeds. The measured data is compared with the 3-D
numerical simulation performed in FLUENT. Standard, realizable and RNG
k-ε models, standard, and SST k-ω and finally RSM turbulence models are
compared for three with near wall treatments, standard wall function,
non-equilibrium wall function and enhanced wall function. The comparison
revealed that for lower velocities the best turbulent model-wall
treatment couple is the realizable k-ε model with Reynolds stress model
with standard wall function, whereas for higher velocities standard k-ε
model turbulence model is observed to be more compatible with
experimental data. The highest pressure value is measured in the front
of the pickup truck and the lowest pressure value is evaluated at the
rim where the windshield and the roof meet.