Computational challenges in high angle of attack flow

Side force occurrence on slender bodies of revolution at high angle-of-attack (AOA > 30°) has long been observed by experimenters. Flow-field features for a slender body at high AOA recently have received considerable attention in the recent year's.These studies demonstrate that flow separating from the body rolls up into a pair of asymmetric vortices between 30° < AOA < 70°.Significant side force results from asymmetric vortices. The magnitude of this side force can equal that of the normal force acting on the slender body, which causes an aircraft to spin or a missile to tumble in situations where these effects are not thoroughly considered as part of the control system design. It is also found that side force distribution exhibited an oscillatory behavior along slender body. In this study, CFD simulations are performed to calculate side force on high angle of attack without any side angle. It is found that this asymmetrical pair of vortices strengths increases as we move backward from the tip and if slenderness ratios is increased then exhibited side force is also increased. The CFD algorithm directly cannot calculate or simulate the side force without side angle because it is symmetric in nature. So in this research study methods are suggested how to calculate the side force with zero side angle. So in this research study computational challenges at high angle of attack are studied and simulated.