Stress-wave balance for measuring the aerodynamic drag force in impulse hypersonic facilities

In the present study, a stress-wave balance and its shield are developed for measuring the aerodynamic drag force of diverse models in the shock tunnel, while the test environment is accompanied by strong vibration interferences and the test time is as short as a few milliseconds. In order to avoid the inertial force interference caused by vibration of the sting support, the balance is suspended in the shield by an innovative polymer wire system. Several commonly used deconvolution algorithms are quantitatively compared, and errors of each algorithm are obtained accordingly. Moreover, the influence of vibration interference of the balance itself on the results of deconvolution calculation is studied. Then, a constraint criterion for the signal length is proposed in the deconvolution calculation process to resolve this problem. Shock tunnel tests are carried out by using a solid hemisphere model and a hollowed Apollo re-entry capsule model. The obtained results show that the deviation between experimental results and reference values is less than 5%.