Numerical Simulation And Research Of The Missle Separated From Aircraft

One of the most challenging problems in aerospace engineering, especially for military vehicles, is the analysis of a store (a weapon, fuel tank, or electronic countermeasures device,for example) that is released from a high-speed aircraft. Store separation analysis typically includes such things as a calculation of the trajectory, the identification of safe separation zones, an assessment of aerodynamic interference, and making sure that collisions are avoided. For many years, physical testing using the actual aircraft and device has been the only method for performing store separation analysis. The cost and risks associated with such tests can be high, however, especially during parametric studies. The method discussed here provides a safer, more cost-effective solution to the analysis needs of aerospace companies involved in this kind of application.The common process of numerical simulation was discussed first. The physical model and governing equation of interferential flow fields was established, and the numerical method was studied. The theory of the dynamic mesh was also introduced. Secondly, a programme to solve the 6 degree-of-freedom (DOF) dynamics equation and the kinematics equation of the missle was made and complied based on the flight dynamics theory. To use this code in the CFD tool, the programme was then rewrited into the prescriptive user-defined-function (UDF) form. Finally, the dynamic mesh technique was used to obtain the parameters of the 6 DOF movement based on the calculation of the initial simulation flowfield which was modeled based on the actual objects. The result of numerical simulation shows that CFD can be applied to analyze complicated flow fields commendably. The aerodynamic interference between airplane and missle was also found to be strong and has a great impact on the separation track. The aerodynamic and trajectory characteristics during the separations of both the controlled missle and the missle launched from the bay with cavity flow characteristic were also studied here using similar method. The problem discusssed here involves many basic issues of fluid dynamics so it has a universal significance in the theory. On the other hand, it has a practical significance in the engineering for it involves the launch of the air based weapon.