Experimental Research On Aerodynamic Heating Environment For Thermal Protection Materials

The aerodynamic heating is extremely serious when flying at high speed.It is not only easy to damage the surface structure of the aircraft,but also can affect the safety of the internal structure of the aircraft seriously,resulting in its unstable operation.Although some experimental methods can simulate the aerodynamic heating environment at this stage,due to limited test conditions and unclear test parameters,the aerodynamic heating environment can be simulated is extremely limited,especially in the case of high enthalpy and low heat flow.Therefore,starting from the aerodynamic heating environment of thermal protection material,combined with the engineering calculation method of aerodynamic heat,the experimental research on aerodynamic heating environment is studied to find a reasonable similar method of test parameters and verified.Firstly,the application of engineering model in different aerodynamic heating environments and aerodynamic heating calculation formulas for typical parts of aircraft are discussed by using aerodynamic heating engineering calculation method.The main parameters affecting aerodynamic heating environment are analyzed,and the roles and meanings of different parameters are clarified.And then a method of simulating the aerodynamic heating environment is proposed,according to the basic principle of the aerodynamic heating environment simulation test is to maintain the consistency of hot-wall heat flow,which is relying on the cold-wall heat flow and recovery temperature of experiment.Furthermore,in this paper,a new type of burner is designed to simulate different aerodynamic heating environments by referring to the test method of engine gas ablation.The burner has stable test condition,good repeatability and convenient parameter adjustment.It can not only simulate the aerodynamic heating environment of the aircraft structure surface,but also simulate the ablation of the inner wall insulation layer of the engine,which provides a guarantee for evaluating ablation performance and aerodynamic heating environment of thermal protection material.Finally,the parameter similarity method proposed in this paper is verified by experiments.The result shows that the parameter similarity method proposed in this paper is feasible both in theory and practical application.In addition,this method is not only convenient for test operation and measurement,but also easy to implement in the experiment.It also broadens the existing test simulation conditions,facilitates the experimental simulation study for the aerodynamic heating environment,and provides new ideas and methods for other ablation tests.