TY - GEN
T1 - Experimental investigation of reynolds number effect on the aeroacoustics fields of a supersonic jet
AU - Ozawa, Yuta
AU - Nonomura, Taku
AU - Oyama, Akira
AU - Yamamoto, Makoto
N1 - Funding Information:
This work was supported by JSPS KAKENHI Grant Number 25709009, 17H03473.
PY - 2019
Y1 - 2019
N2 - The flow structure and near field acoustic profile of a supersonic jet at a Mach number of 2.0 and Reynolds numbers of 105 and 106 were investigated by particle imaging velocimetry, schlieren visualization and acoustic measurement using a microphone. The effect of the disturbance in the shear layer was also investigated. In the case of higher Reynolds number jet, the presence of disturbance does not significantly affect the flow and acoustic fields because the shear layer state has already been turbulent even without the disturbance. However, presence of disturbance significantly affects the flow and acoustic fields in the case of moderate Reynolds number jet (Re=105) because the initial condition of the shear layer without disturbance is laminar and disturbance promotes the turbulent transition which has the strong influence on flow and acoustic fields. The sound pressure level decreases with adding disturbance because the promoted turbulent shear layer is smoothly growing instead of rapid growth in the vicinity of the transition which leads to strong acoustic wave emission.
AB - The flow structure and near field acoustic profile of a supersonic jet at a Mach number of 2.0 and Reynolds numbers of 105 and 106 were investigated by particle imaging velocimetry, schlieren visualization and acoustic measurement using a microphone. The effect of the disturbance in the shear layer was also investigated. In the case of higher Reynolds number jet, the presence of disturbance does not significantly affect the flow and acoustic fields because the shear layer state has already been turbulent even without the disturbance. However, presence of disturbance significantly affects the flow and acoustic fields in the case of moderate Reynolds number jet (Re=105) because the initial condition of the shear layer without disturbance is laminar and disturbance promotes the turbulent transition which has the strong influence on flow and acoustic fields. The sound pressure level decreases with adding disturbance because the promoted turbulent shear layer is smoothly growing instead of rapid growth in the vicinity of the transition which leads to strong acoustic wave emission.
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U2 - 10.2514/6.2019-2767
DO - 10.2514/6.2019-2767
M3 - Conference contribution
AN - SCOPUS:85095967639
SN - 9781624105883
T3 - 25th AIAA/CEAS Aeroacoustics Conference, 2019
BT - 25th AIAA/CEAS Aeroacoustics Conference, 2019
PB - American Institute of Aeronautics and Astronautics Inc, AIAA
T2 - 25th AIAA/CEAS Aeroacoustics Conference, 2019
Y2 - 20 May 2019 through 23 May 2019
ER -