Abstract:
Symmetric and Asymmetric vortices were captured on the leeside of forebodies and fuselage of supersonic transport aircraft, at high angle of attack, without perturbing the flow by sideslip angle or geometric perturbation. Fluent was used as a tool for numerical simulations and extensive simulations and analysis have given into the behavior of the flow field and the onset of vortex asymmetry. Silent features of the flow at high angle of attack were highlighted. Based on the experimental and numerical work done so far, summary of different school of thoughts about asymmetric flow was presented. Sophisticated techniques used to control the asymmetric flow were also summarized. Different computational techniques used to simulate the asymmetric flow were described, along with advantages and disadvantages of these techniques. Three dimensional, coupled implicit, flux vector splitting, Reynolds Average Navier Stokes equations were used to simulate the vortical flow. A comparison of this technique with other techniques previously used was done and some of the details of graphical visualization of vortex pattern were also described. Unsteady vortex- shedding at high speed was simulated at high angle of attack. Mathematical modeling done for the simulation of vortical flow, in particular, turbulence modeling set to explore the flow features in viscous sub-layer. Growth rate maps of symmetric and asymmetric vortices were presented and the side force generated due to asymmetric vortices was also calculated. Based on the numerical and experimental results, it was concluded that there is a need to find the relationship between the numerical and experimental results of vertical flow around aircraft at high angle of attack. It was also observed that the onset angle of asymmetry can be delayed by increasing the nose-semi apex angle.
Page(s):
35-45
DOI:
DOI not available
Published:
Journal: Proceedings of 4th International Bhurban Conference on Applied Sciences and Technology, Volume: 0, Issue: , Year: 2005