Numerical investigation of store separation from airplane wing, and study of the parameters, affecting the fall amount of store

This paper deals with numerical simulation of store separation from aircraft wing. In this study the effects of 4 variables, wing aspect ratio, store aspect ratio, forward and backward ejector force have been studied and analyzed. Unstructured tetrahedral grid was used for flow field discretization. Flow governing equations are Euler equations which are solved simultaneously with six degrees of freedom code for rigid body motion to obtain the trajectory of store. The results of numerical solution method were compared with experimental data provided by Arnold engineering development center and a good match was observed. To determine the number of numerical solutions needed to evaluate the effects of parameters, Box-Behnken method, which is one of the conventional methods of experimental design, was used. By these results, the model of fall amount proposed. It was found that the most important determinant of the fall is store aspect ratio and wing aspect ratio has the least impact.