Determination method for thermal test condition of the tip wedge structure heated by high temperature gas flow

In view of to the traditional thermal test method based on the cold wall heat flux, a determination method based on the curves of the hot wall temperature and heat flux varying with time was proposed. Certain modification to the heat flux was made based on the deviation between the target and measured wall temperatures, in order to eliminate and remedy the test error during the earlier stage. And it determined the temperature of gas flow exactly and rapidly by interpolation in the database of the 300K cold wall heat flux, which solved one of the problems of transient thermal test along the trajectory. The heat flux database of tip wedge structure with variant gas flow rate and temperature was set up by CFD numerical analysis. The aerodynamic heating required for simulation of 9 typical conditions along a hypersonic flight trajectory was obtained and proved to be quite accurate for the requirements of engineering test by numerical simulation with the average error of heat flux of 4.5% in the stagnation point region, 4.6% in the rear plate region, and both maximum error of no more than 8%. The precision meets the requirements of engineering test. Moreover, transient thermal analysis results show that in forty-fifth seconds the biggest temperature gradient is 21K/mm and 18K/mm separately at 1mm and 10.1mm distance from the stagnation point, meeting the demand of high temperature gradient effect of aerodynamic heat.