Numerical simulation of aircraft wake vortex evolution and wake encounters based on adaptive mesh method

The fast and accurate simulation of aircraft wake vortices evolution and safety assessment of wake encounters are important in identifying the hazard zone of wake vortices, reducing wake separation, and increasing the capacity of airports. However, numerical simulation of wake vortices often takes a lot of time due to a large number of grids. In order to reduce the computation time, Solution-Based Dynamic adaptive mesh method is applied to compute the wake vortex evolution using FLUENT. Three cases with different ambient turbulence intensities are carried out with the large eddy simulation (LES) based on adaptive mesh. The numerical result shows that refiner meshes in the region of the vortex core generated by adaptive mesh method can more effectively capture the dynamics of vortices, identify more secondary vortices and reduce the numerical dissipation due to more compact vortex core resolution. Then, the rolling moment of the following aircraft is calculated and the hazard zone is identified for the aircraft pairing of A340 and A320. The results show that the safety of wake encounters has a close relationship with ambient turbulent intensity and development of vortex instability.