TY - JOUR
T1 - Experimental Investigation of Noise and Flow Characteristics of Supersonic Underexpanded Jet Interaction with a Coannular Tube
AU - Iraqi, Mohammed Khalil Ibrahim
AU - Miya, N
AU - Mori, K
AU - Nakamura, Y
PY - 2015
Y1 - 2015
N2 - In the present study, experiments were conducted to investigate the interaction of supersonic underexpanded jet delivered from a convergent nozzle with a coannular tube on both the flowfield and noise emission. The effects of varying the tube length, L, and diameter, D, were investigated. The most pronounced noise reduction was observed at D/D-j = 2.2 at a jet nozzle pressure ratio (NPR) of 5, where the noise emission was reduced by approximately 30 dB compared with the baseline jet. Considerable sound pressure level (SPL) reduction over the measured frequency range was observed and the screech tone was completely suppressed. The schlieren photographs revealed that the shock-cell structure of the baseline jet disappeared at D/Dj = 1.9 as well as for higher values of D/D-j outside the tube. Detailed experimental investigations were carried out to explain the reduction in the noise radiated at D/D-j = 2.2. From these results, it was made clear that the Mach disk for the case of D/D-j = 2
AB - In the present study, experiments were conducted to investigate the interaction of supersonic underexpanded jet delivered from a convergent nozzle with a coannular tube on both the flowfield and noise emission. The effects of varying the tube length, L, and diameter, D, were investigated. The most pronounced noise reduction was observed at D/D-j = 2.2 at a jet nozzle pressure ratio (NPR) of 5, where the noise emission was reduced by approximately 30 dB compared with the baseline jet. Considerable sound pressure level (SPL) reduction over the measured frequency range was observed and the screech tone was completely suppressed. The schlieren photographs revealed that the shock-cell structure of the baseline jet disappeared at D/Dj = 1.9 as well as for higher values of D/D-j outside the tube. Detailed experimental investigations were carried out to explain the reduction in the noise radiated at D/D-j = 2.2. From these results, it was made clear that the Mach disk for the case of D/D-j = 2
M3 - Article
SN - 0549-3811
JO - Transactions of the Japan Society for Aeronautical and Space Sciences
JF - Transactions of the Japan Society for Aeronautical and Space Sciences
ER -