Research on wind tunnel test technology of sonic boom measurement based on probe

Wind tunnel test is an indispensable technical means to carry out sonic boom research. Accurately obtaining sonic boom signals with weak signal attributes from complex wind tunnel test environment is the key of wind tunnel test technology. In order to study the influence of the test environment on the accurate measurement of sonic boom signal in the transient supersonic wind tunnel, a small transient trans-supersonic wind tunnel was used to develop a test device with a needle probe with the characteristics of minimizing interference. A dual motion test system with independent motion of probe and model was established, and the sonic boom measurement technology based on probe was developed. Taking a typical cone-cylinder model as the research object, the differences of the complete sonic boom signals obtained by the two test methods of fixed probe and moving model and fixed model and moving probe are compared, and the sonic boom propagation law of cone-cylinder model and the influence of wind tunnel background flow field on sonic boom measurement are studied. The results show that: Compared with the two test methods of fixed model and moving probe, the former will cause the distortion of sonic boom signal, which leads to more serious distortion of sonic boom signal, while the latter is smoother and more accurate, which is a relatively more reliable test method; The background flow field distribution in wind tunnel has a significant influence on sonic boom signal measurement. It is necessary to master the background flow field distribution in wind tunnel in detail and keep it stable as much as possible. On this basis, the positions of model and probe in wind tunnel and the relative positions of model and probe should be strictly selected.