Effects of nose and afterbody of blunt body on side force

The random asymmetric flow over its blunt-nose body is generated when it flies at high angles of attack, thus resulting in unexpected side-forces, which leads to the trajectory deviation. The pattern of asymmetric flow and its corresponding side-force are determined by attaching an artificial perturbation on the nose of the blunt-nose body at high angle of attack, which is helpful to improve the flight characteristics and maneuverability of blunt-nose body. Based on the major control effect of the artificial perturbation on the asymmetric flow, the effect of the afterbody of the model is discussed in this paper. Experimental tests are conducted to investigate influence factor of side force at high angle of attack 50° and Re_D=1.54×10⁵, with the perturbation locations of circumferential angles 90°/270° and meridian angle 10°. It is found that the effect of afterbody is still existent as an important effect factor, which effects the major control of the nose of the model to the asymmetric flow. Though the status of the main control from perturbation cannot be changed by the afterbody, the accuracy of control of perturbation on the nose is decreased. Therefore, the processing quality of afterbody should be enhanced to intensify the major effect of artificial perturbation on the asymmetric flow over the blunt-nose body.