Turbulence measurements in a resonance tube

Experimental investigations of acoustically induced turbulence in a resonance tube have been performed. Frequency (f) and sound pressure level (I_p) effects have been studied. Measurements were made at various spatial locations on loops and nodes. Sampled data were processed to estimate the characteristics of turbulence. It is found that the acoustically induced turbulence appears when I_p exceeds 160 dB under the experimental conditions of f = 680-2740 Hz and I_p = 160-166 dB. The turbulent spectrum (F) and the wave number (κ) are found to satisfy a power law F ∝ K^s with s {reversed tilde equals} -1·6 to - 2·1. The r.m.s. turbulent velocity ( u ̃) is experimentally found to have an I_p ^{1 2} dependence, yet is relatively insensitive to the variation of f. Throughout the whole measuring range of f and I_p, the rate of energy dissipation per unit mass (ε) is estimated to be in the order of 10⁶-10⁷cm²/s³.