Jet flow involved numerical simulation of missile launching from the R/S UAV

Reconnaissance and Strike Unmanned aerial vehicles (R/S UAV) which is the combination of reconnaissance UAV and strike UAV platform has played an important role in the Battlefield. After founding ground targets, R/S UVA can distinguish and attack the most threatening one rapidly with carried missile under wings. R/S UAV platforms usually gets a relatively small fuselage which might be threatened by the unsteady aerodynamic forces and hightemperature engine jet flow during missile launch. In order to study the security of R/S UAV during the launch, the process is simulated by using the method of the computational fluid dynamics (CFD). Combination of missile engine jet flow and aircraft flow fields was proposed in the simualtion to improve accuracy.The aerodynamic and flight behavior of UAV and missile during the transition process are simulated. Factors like aerodynamic interference, the rules of missile movement and the interaction between UAV and missile jet flow are considered in the simulation. Unstructured dynamic mesh is used coupled with an unsteady flow solver, and a 6DOF model is fully integrated into the CFD solution procedure to determine the body dynamics. The results obtained for a time-accurate missile launch from the R/S UAV by the developed numerical methods are presented. The investigation show that the interference between missile and UAV would be much less because of the missile engine jet flow, which means there are low collision risks between R/S UAV and missile under most launch conditions, the flight performance of R/S UAV is not affected by missile jet greatly. However the erosion threaten would be posed to R/S UAV by high temperature missile jet flow under some certain conditions.