F-22 Aircraft

F-22 Aircraft CFD Simulation, ANSYS Fluent

Description

This project simulates an F-22 aircraft using ANSYS Fluent. The geometry was designed in SpaceClaim and meshed using Fluent Meshing, generating approximately 5 million polyhedral elements. Given the high Mach number of 0.4, the simulation was carried out using the density-based solver, with the flow assumed to be steady.

A related wing lift-to-drag ratio optimization of this aircraft using RBF Morph is also available and can be viewed here.

Methodology

The aircraft surface was defined as a wall, with all remaining boundaries set as pressure far-field conditions at a Mach number of 2. The SIMPLE algorithm was used with an explicit formulation, standard initialization, and the k-ε Realizable turbulence model. The working fluid was treated as an ideal gas (air).

Conclusion

The simulation produced a drag force of 74.067622 kN. Since the model was solved using symmetry, doubling this value yields approximately 148,135.244 N (≈148 kN) — close to the F-22's known engine thrust of roughly 156 kN, confirming a relatively accurate simulation with a percentage error of:

Percentage Error = (|156,000 − 148,135.244| / 156,000) × 100% ≈ 5.04%

The velocity contour shows the distribution of velocity magnitude around the aircraft, with higher velocities concentrated near the wings and tail. The pressure contour reveals higher-pressure regions at the wing leading edges and nose, with lower-pressure regions along the upper wing and tail surfaces. A pressure coefficient plot, taken on a plane 5 meters from the aircraft's center, illustrates the relative pressure distribution across that plane — positive values indicating high-pressure regions and negative values indicating low-pressure regions relative to freestream conditions.

Overall, the close agreement between the simulated drag force and the F-22's actual engine thrust — within roughly 5% error — confirms the simulation's accuracy, and the resulting velocity, pressure, and pressure coefficient contours provide a clear picture of flow behavior around the aircraft, suitable for further design analysis and optimization work.