F1 CAR SIMULATION

In one of my previous posts, I covered a full body automotive steady state simulation with resolved boundary layers, whose non-dimensionless wall distance y+ was less than 1. In the following simulation, I have used wall function to run a kOmegaSST turbulence model on a boundary layer-less grid. Again, a steady state solver was used to compute the force Coefficients of a formula 1 car. The car model was downloaded from Grab cad: https://grabcad.com/library  The average value of the drag coefficient was found to be 0.72. The converged drag plot can be accessed below. Here is a worthwhile observation, while using snappyHexMesh tool to create a mesh which employs wall function, sometimes it is required that at least one boundary layer be extruded in order to fall within the range 30 < y+ < 300. Again, this depends on the nature of the background mesh and the level of refinement used inside the fluid domain. Kindly write to me if you require assistance in the case set-up.

The turbulent kinetic energy 'k' and the specific rate of dissipation ''ω'  is calculated using the formula:

Where L is the wheel base length.
Below is a cross-sectional representation of Velocity vector U. 

              Figure No.1: Cross-sectional U

Full extension of the Velocity U is captured in the image below
    Figure No.2: Free stream U across the domain
       Figure No.3: The turbulence kinetic energy 'k'

                  Figure No.4: Pressure contour 'p'

                                Figure No.5: Drag Coefficient (Scroll to view the complete image)
                 Figure No.6: Pressure Residual

                  Figure No.7: Residuals

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