Research On Identification Method Of Hypersonic Flight Environment Parameters

With the development of aerospace technology,near space vehicle has been a research focus in various countries.Hypersonic vehicles face a complex flight environment,but there is still a lack of in-depth understanding and research on it due to the limitations of the detection means.In this paper,the identification methods of aerodynamic heating environment and atmospheric environment for hypersonic vehicles are presented.Firstly,both one-dimensional and two-dimensional identification models and algorithms are established for the typical hypersonic aerodynamic heating environment in consideration of measurement noise and measure point optimization.The numerical simulations of the models and algorithms are performed,which are proved effective.And the one-dimensional identification model is used to improve the heat measurement method of film resistance thermometers.Then,for the aerodynamic heating identification in complex flight environment,the three-dimensional effect of heat conduction is corrected by the optimized artificial neural network,which greatly improves the identification accuracy of stagnation heat flux.And the thermal conductivities of multilayer heat-resistant materials are identified in consideration of thermal properties changes of the materials.Besides,a simplified one-dimensional heat flux identification model with ablation is established,and an example is given to validate the correctness of the model and algorithm.Finally,the identification method of atmospheric environment for hypersonic vehicles is studied.The identification model and its algorithm are established based on the theory of gas dynamics.Then the paper designs a numerical simulation example of a ball to validate the accuracy of the program and modifies the delay of surface pressure measurements.The numerical simulation results in the paper show that the methods of identifying hypersonic aerodynamic heating environment and atmospheric environmental parameters are accurate and effective,which are also instructive for engineering application.