Shock oscillation in highly underexpanded jets Project supported by the National Natural Science Foundation of China (Grant No. 11602028) and the Science and Technology Project of General Administration of Quality Supervision Inspection and Quarantine of China (Grant Nos. 2017QK119 and 2017QK188). |
(color online) (a) Amplitude of screech frequencies, and (b) amplitude ratio between the axisymmetric mode of f = 5.298 kHz and screech tone. The screech frequencies presented here are 37.086 kHz, 34.437 kHz, 31.787 kHz, and 29.801 kHz for NPR = 5.60, 7.47, 9.34, and 11.21, respectively. |