Sports Coupe Aerodynamic Performance Analysis
Examining body flow, wheel-region disturbances and wake velocity deficits alongside aerodynamic load statistics.
00 / Understanding full-vehicle aerodynamics
Engineering question
Body, underbody and wheel-region flows jointly influence coupe aerodynamics. Exported flow views and load statistics provide a baseline for examining roof acceleration, the low-speed rear wake and wheel-region disturbances before evaluating geometry changes.
What do drag and vertical loads reveal at the configured condition, and which flow regions merit closer inspection?
120 km/h
configured freestream speed
0.4442
mean drag coefficient
4,575
samples in the statistics window
25%
final sample fraction
01 / Establish conditions and reference quantities
A consistent condition for the aerodynamic baseline
The current configuration specifies zero angle of attack and sideslip. The geometry includes the body and wheel regions. Longitudinal and horizontal flow sections and near-body vortex structures help connect local flow behavior with integrated aerodynamic loads.
- Freestream speed
- 120 km/h (33.33 m/s)
- Flow direction
- 0° angle of attack · 0° sideslip
- Air density
- 1.225 kg/m³
- Reference area
- 1.8559 m²
- Reference length
- 4.2341 m
- Run configuration
- STAR-CCM+ · incompressible DDES
- Statistics window
- Final 25% · 4,575 samples
The run configuration identifies STAR-CCM+ incompressible DDES. This review uses existing exports; the solver was not rerun.
02 / See the flow behind the integrated loads
Roof acceleration, wheel disturbances and a low-speed wake
The longitudinal section shows roof-region acceleration and a low-speed rear wake. The horizontal section shows nonuniform flow around the wheels and downstream.
What to look for
- 01Longitudinal section: acceleration above the roof and the velocity deficit behind the body.
- 02Horizontal section: nonuniform velocity around the wheels, along the sides and in the downstream wake.
- 03Near-body structures: inspect the Q-criterion isosurface without inferring pressure or drag values from render colors.
03 / Examine means and fluctuations together
Near-zero mean lift still leaves substantial load variation
Mean lift is slightly negative and close to zero, while lift fluctuation RMS exceeds its absolute mean. Mean load alone does not characterize load stability.
| Load | Mean / N | Fluctuation RMS / N | Mean coefficient |
|---|---|---|---|
| Drag | 561.03 | 17.87 | Cd = 0.4442 |
| Lift | −10.35 | 49.18 | Cl = −0.00819 |
Window coordinates are 13,726–18,300; their mapping to physical time in seconds is not established. Fluctuation RMS measures variation about the mean, not mean error or a confidence interval.
Engineering interpretation: lift fluctuation RMS exceeds the absolute mean lift. The mean alone misses vertical-load variation in this window; inspect the full history and statistical convergence as well.
04 / Separate available results from validation
Building evidence for a defensible geometry comparison
Existing images and statistics support inspection of flow and loads at a single condition. Evaluating a geometry change requires consistent reference quantities, boundary conditions and comparable statistics windows.
Interpretation and limits
Values come from existing statistics. Solver logs, mesh and time-step independence, and experimental comparison have not been verified. Reference quantities reflect the current case configuration and still require comparison with original solver settings. Lift follows the exported coordinate convention (+Z in the postprocessing configuration), not axle load distribution. These results are not certified road performance.
05 / Engineering takeaways
Three findings to carry into the next analysis
01
Locate the flow regions
The roof, wheels, underbody and wake define the next inspection areas. Use the flow field to guide geometry changes.
02
Read means and fluctuations
Drag and lift statistics quantify the baseline. Near-zero mean lift alone does not establish stable vertical loading.
03
Compare consistent conditions
Complete mesh, time-step and statistical convergence checks before comparing geometry options. This single condition establishes no drag-reduction benefit.
Study basis
Prepared from existing c002/r002 velocity sections, Q-criterion isosurfaces and load statistics, with conditions and reference quantities from the current configuration. The solver was not rerun for this page.
Need to assess full-vehicle aerodynamics?
Turn flow observations into the next design decision.
Inspect rear pressure recovery, wheel-region and underbody flow, complete numerical verification, then compare geometry options under consistent boundary conditions using drag, vertical load and fluctuation metrics.