Research And Implementation Of Thermal Environment Prediction Platform For Complex Shape Aircraft Based On Surface Flow Field Topology

Aerodynamic heating environment prediction is a key problem in engineering calculation of hypersonic vehicle with complex shape.Using efficient approximate aerothermal engineering calculation method is the first choice for thermal prediction in early design stage of aircraft.However,the traditional engineering methods have low adaptability to the shape,which requires manual division and approximation.Programs with different shapes can not be reused directly,and the investment is high and the return is low.The online visualization calculation platform of aerothermal environment established in this paper is an extension of the aerothermal method.It has strong adaptability to the shape,high level of automation,and improves the efficiency of the shape design work.In this paper,based on the streamline tracing method,the aerodynamic heat is calculated by using the attachment line characteristics of the flow field and the stagnation point heat flux compute method,the calculation method of the streamline is improved,and automatically extract the attachment line characteristics is implemented.The algorithm is applied to many shapes,and its validity and applicability are analyzed.The results show that the improved aerothermal method has reasonable surface heat flux distribution and moderate accuracy,which can meet the needs of early design of aircraft with complex shape.The fast calculation platform for aerothermal environment established in this paper is a practical application of Engineering algorithm,which has the characteristics of general,fast and reliable.Firstly,this paper introduces the research and development of the platform from the aspects of technology selection,data structure organization,key technology of algorithm implementation and detailed design of the system.Then the function test and performance test of the platform are carried out.The test results show that the platform has friendly interface,stable operation and excellent efficiency.The performance of the system is improved by using multi-thread concurrency technology.The aerodynamic thermal environment prediction platform based on flow field topology is analyzed by case study and system test.The results show that using geometrical engineering flow field can achieve high accuracy for simple shape similar to blunt biconical cone,and the total time consumed is seconds.And using numerical inviscid flow field has high accuracy for complex shape similar to space shuttle,the total time consumed is mainly determined by the time consumed in calculating numerical inviscid flow field with minutes.When using geometric engineering flow field,the time-consuming preprocessing and streamline data can be reused to reduce 90% of the total time-consuming and greatly improve the computational efficiency.