Aerodynamic Force Measurement in a Large-Scale Shock Tunnel
Force tests were conducted at the long-duration-test shock tunnel JF12, which has been designed and built in the Institute of Mechanics, Chinese Academy of Sciences. The performance tests demonstrated that this facility is capable of reproducing a flow of dry air at Mach numbers from 5 to 9 at more than 100 ms test duration. Therefore, the traditional internal strain-gauge balance was considered for the force tests used in this large impulse facility. However, when the force tests are conducted in a shock tunnel, the inertial forces lead to low-frequency vibrations of the test model, and its motion cannot be addressed through digital filtering because a sufficient number of cycles cannot be found during a shock tunnel run. The post-processing of the balance signal thus becomes extremely difficult when an averaging method is employed. Therefore, the force measurement encounters many problems in an impulse facility, particularly for large and heavy models. The objective of the present study is to develop pulse-type sting balance by using a strain-gauge sensor, which can be applied in the force measurement that 100 ms test time, especially for the force test of the large-scale model. Different structures of the S-series (i.e., sting shaped balances) strain-gauge balance are proposed and designed, and the measuring elements are further optimized to overcome the difficulties encountered during the measurement of aerodynamic force in a shock tunnel. In addition, the force tests were conducted using two large-scale test models in JF12, and the S-series strain-gauge balances show good performance in the force measurements during the 100 ms test time.
This work was supported by the National Natural Science Foundation of China (Grant No.11672357).
- 1.P.J. Arrington, R.J. Joiner, A.J. Henderson. Longitudinal Characteristics of Several Configurations at Hypersonic Mach Numbers in Conical and Contoured Nnozzles, NASA TN D-2489 (1954)Google Scholar
- 2.L. Bernstein. Force Measurement in Short-Duration Hypersonic Facilities. AGARDograph No. 214 (1975)Google Scholar
- 9.S.R. Sanderson, J.M. Simmons, S.L. Tuttle, A drag measurement technique for free-piston shock tunnels, AIAA Paper 91-0540 (1991)Google Scholar
- 11.F. Seiler, G. Mathieu, A. George, J. Srulijes, M. Havermann, Development of a free flight force measuring technique (ffm) at the isl shock tube laboratory, in 25th International Symposium on Shock Wave, Bangalore, India, 2005Google Scholar
- 12.P. Wey, M. Bastide, B. Martinez, J. Srulijes, P. Gnemmi, Determination of aerodynamic coeffcients from shock tunnel free- flight trajectories, in Proceedings of the 28th Aerodynamic Measurement Technology, Ground Testing and Flight Testing Conference, New Orleans, USA, 2012Google Scholar
- 13.B. Martinez, M. Bastide, P. Wey, Free-flight measurement technique in shock tunnel, in Proceedings of the 30th Aerodynamic Measurement Technology and Ground Testing Conference, Atlanta, USA, 2014Google Scholar
- 15.H. Tanno, T. Komuro, K. Sato, K. Itoh, T. Yamada, Free-flight tests of reentry capsule models in free-piston shock tunnel, AIAA Paper 2013-2979 (2013)Google Scholar