Aerodynamic Heat Calculation Of High Speed Rocket With Heat Protection Layer

In this paper,the aerodynamic thermal protection of hypersonic complex-shaped rocket is calculated and studied.The thermal distribution of the heat-resisting layer under nonstationary state is obtained through coupling engineering algorithm and numerical algorithm to solve aerothennal parameters of complex-shaped rocket with structure heat transfer coupled.Hypersonic aerodynamic heat calculation,mainly including engineering and pure numerical algorithms,is a difficult problem in hypersonic flow research nowadays.Inspite of high accuracy,the former does not apply to calculation of aerodynamic thermal protection of complicate shape.Pure numerical algorithm of solving equation of Navier-Stokes has good adaptability to complicate shape and a certain calculation accuracy but requires a high-qualitied computer and the efficiency of calculation is low in need of a long time.Based on the advantages of the two methods,the numerical solution of inviscid outflow is adopted as parameters of the outer edge of the boundary layer while aerodynamic heating in the boundary layer is calculated by engineering algorithm,and a set of aerodynamic heat calculation method which is suitable for complex high-speed contours with low computational cost and high precision is developed.In this paper,the method is divided into three parts.Firstly,the numerical solution of the inviscid outflow is calculated by pure numerical algorithm,discrete data of Euler Equation is based on the method of finite volume,spatial discretization uses the scheme of Second Order Upwind Roe,and temporal discretezation selects the five-step scheme of Runge-Kutta.Secondly,thermal flux in boundary layer is calculated by engineering algorithm,which is divided into stagnation point where calculation formula of the Fay-Riddell with high engineering precision is selected and nonstationary point where Plate heat flux calculation is selected.Finally,a one-dimensional thermal conduction hypothesis is carried out,ignoring the contact thermal resistance between the layers,and the thermal flux obtained by the engineering algorithm is used as the boundary condition to solve the differential equation of heat conduction to realize coupling between the structural heat transfer and the pneumatic heating.At last the temperature distribution of heatshield under the long-endurance state is obtained.The aerodynamic thermal environment of the classical blunt cone model is calculated In this paper.It is founded that the thermal flux of the blunt cone surface is in good agreement with the experimental results,which verifies that the effectiveness of the method of the aerodynamic thermal fast calculation coupling viscoelastic solution and the engineering algorithm.Furthermore,the numerical simulation of one-dimension thermal conduction equation is carried out for plate thermal conduction,and the calculated results are compared with the analytic solution.The results show that the one-dimension thermal conduction calculation method has high accuracy.Ultimately,the aerodynamic thermal environment of the hypersonic projectiles was calculated related to heatshield.The influence of the thermal conduction of the outermost layer and the thermal diffusivity of the main thermal layer on the aerodynamic heating of the projectiles was analyzed.The results of the analysis of complex-shaped rocket show that the method can meet the requirements of engineering calculation and the obtained effective rules can provide some references for hypersonic aerodynamic thermal protection...