Application of method of deconvolution at temperature measurements in high-enthalpy impulse wind tunnels

Abstract

In practice of experiment, we are faced with the distortions caused by measuring equipment, especially on a limit of its resolution. Sometimes not the equipment but the investigated process itself gives the grounds for distortion of the registered data, for example, at photography of quickly moving objects. Other examples of distortion of data are measurements of temperatures and forces in aerodynamic wind tunnels.To minimize an influence of instrumental function (response on δ-function) of the device on measurement accuracy, problem is most often reduced to the solution of the integral equations, usually, with convolution kernels.The solution of these equations is called problem of deconvolution. The methods and algorithms of the solution of some tasks of the signals processing at experimental researches of high flow speed are presented in this paper. The regularization algorithm of the solution of problem of deconvolution, adapted to the level of experimental noise, is described. Results of numerical simulation of thermocouples lag and temperature correction at restrictions of time resolution of the temperature gages and short-term process are given.Experimental definition of the thermocouples instrumental function was carried out in experiments with constant thermal loading.It was shown that application of such approach allows to minimize influence of experimental noise at treatment of signal, and to receive correct results at measurements of temperatures in a hypersonic wind tunnel.