Calculating Method Of Aerodynamic Heating For The High Velocity Projectiles Of Complicate Shape

For research on the computational method of aerodynamic heat for the high velocity projectiles with complicate shape, using numerical solution outside the boundary layer combined with engineering method for inner boundary layer. This computational method can apply to rapid calculation of aerodynamic heat for the high velocity projectiles and give the surface heat flux distribution. Computing results can provide technical support for high velocity projectiles design about lectotype and thermal protection of aerodynamic heat.Engineering method and numerical method have each advantage in aerodynamic heating for high velocity projectiles with complicate shape. Engineering method solving the aerodynamic heat can only apply to the simple shape. The numerical method can calculate the aerodynamic heat of complicate shape by solving the Navier-Stokes equation with low computation efficiency. We combined the two methods.The new methods can also have the advantages of high computational efficiency and high accuracy. In this way, the aerodynamic heat of the projectiles which has the complicate shape can be accurately calculated and the computational efficiency can be guaranteed.First, generating high precision structured grids for outflow field of a complex shape projectile.The spatial discretization of Euler control equations is obtained by a finite volume method in the second-order AUSM scheme and the time discretization of Euler control equations is obtained by the Runge-Kutta scheme to get the flow parameters of outer boundary layer. Then write the interface program to couple numerical method with engineering method. The computational results of boundary layer edge are used as input parameters of engineering method to find the position of the stagnation points. The whole flow field is divided into two areas.Fay-Riddell stagnation point heat flux equations are used in the stagnation region and the formula of heat flux density of laminar flow plate with reference enthalpy correction are used to solve heat flux distribution in the non stagnation region, which is based on local similarity principle.In order to validate our new method,we simulate two simple numerical example of blunt cone and biconic. The calculated results are compared with the experimental data, and the results are in good agreement with the experimental data. This proves that a combination of numerical algorithm and engineering algorithm has high precision and efficiency. At the last, the method is applied to the projectiles with complex shape to calculate the surface heat flux distribution. The analysis of calculation results proves that the method is suitable for high speed projectiles with complex shape.