Experimental verification of the method of calculating the flow parameters in the test section of the hotshot wind tunnel

Calculated parameters of the gas flow in the test section of a high-enthalpy short-duration wind tunnel (IT-302M hotshot wind tunnel) are compared with experimentally determined values. It is demonstrated that the differences in flow characteristics in the test section measured by two methods [flow rate determined by the method of flask filling and physical velocity determined by particle image velocimetry (PIV)] and the calculated values is within several percent. The experimental results show that the assumptions taken for calculating the flow parameters in the test section ensure a fairly accurate description of the processes in the gas-dynamic duct of the hotshot wind tunnel. The most significant differences between the calculated and experimental values are found to be induced by two factors: neglect of heat losses from the test gas (gas flow) to the walls of the first settling chamber and uncertainty in reconstructing the pressure level in the first chamber at the time $t=0$.