Incoming flow parameter determining method applicable to appearance of body of revolution

Abstract

Provided is an incoming flow parameter determining method applicable to an appearance of a body of revolution. The method comprises the steps of 1, building a surface pressure approximation model applicable for the appearance of the body of revolution, wherein firstly a surface pressure computational formula is determined, and surface pressure is expressed as a sum of a product of incoming flow dynamic pressure qc and a pressure coefficient Cpi and incoming flow static pressure p infinity; then a polynomial form is adopted to express the pressure coefficient Cpi, and polynomial factors are a flight attack angle alpha, a sideslip angle beta and an incoming flow pressure ratio R; finally the factors in the polynomial are obtained through numerical fitting, regression or a least square method to surface measuring point pressure of the body of revolution in multiple sets of states; 2, obtaining the surface measuring point pressure of the body of revolution in a flight experiment, conducting back calculation according to the surface measuring point pressure combining the approximation model, and accordingly obtaining an incoming flow parameter. According to the incoming flow parameter determining method applicable for the appearance of the body of revolution, the model can be used for an embedded air data system, and the prediction accuracy of the system can be effectively improved.

Description

technical field [0001] The invention relates to a surface pressure approximation model suitable for the shape of a spinning body, which can be applied to embedded air data systems (FADS) such as rockets, and belongs to the field of aircraft flight state measurement. Background technique [0002] In view of the high-temperature heating effect of hypersonic speed, the embedded air data system (FADS) is necessary on the hypersonic vehicle. High precision has always been the goal pursued by the air data system. In addition to the function between parameters, the theoretical method is generally used to establish a model from flight parameters to surface pressure. When using it, the corresponding flight parameters are obtained by inversely solving the overdetermined equations composed of different pressure measurement point pressures. [0003] The accuracy of the embedded air data system under the theoretical model is directly related to the surface pressure model, and the higher ...

AI Technical Summary

Problems solved by technology

At present, the atmospheric data system based on the neural network is generally used for the spiral body, but it is difficult for this system to guarantee the measurement accuracy of the disturbance.

Images