CFD Simulation Projects by ANSYS Fluent — Ep 11
Car (AUDI) External Flow CFD Simulation, ANSYS Fluent software
- Episode
- 11
- Run Time
- 18m 36s
- Published
- Apr 05, 2025
- Course Progress
- 0%
Description
Using ANSYS Fluent software, this project will investigate an incompressible isothermal air flow next to an Audi-A4-2017 automobile. Testing is done at a maximum speed of 77.76 m/s, which is fairly high, and the drag force value is derived.
Methodology
Design Modeler software creates the 3-D geometry of the model. The current model has a rectangular cubic computational domain measuring 20 m * 10 m * 5 m for airflow, in which a AUDI car sits.
Unstructured mesh type is used; ANSYS Meshing tool was used to complete the model meshing. The element number is 4,950,697, and the meshing accuracy is better near the vehicle surfaces.
Conclusion
Results might be seen via post-processing once the solution has converged. The drag value was tracked during the solution iterations to guarantee a good convergence.
The solution in this work was a convergent one when the drag force attained a constant value and the residuals fell below 10-5 values. Most drag forces are pressure forces, according to the findings; the proportion of frictional forces in drag is small.
The front and back of the car experienced the most pressure, which resulted from the least velocity contour. The velocity vectors show flow separation at the front and rear of the car.
This separation is more concentrated in the front of the automobile and is wider in the back of the vehicle, which can be ascribed to the broader geometry in the back of the car. Though in places with more angle to the flow direction, this pressure is larger.
Pressure on the surface increases the more perpendicular it is to the flow. The pressure on the sharp edges, particularly on the front wheel and the edge of the front glass, is negative as well; the speed in these regions has risen, which may be ascribed to the fast shift in the flow angle caused by the change in fracture.
The Shear force contours also indicate that the flow separation began when these contours changed sign. The drag force calculated in this issue is 1684.74 Newtons.