A Study on Aero-noise of Heat Exchanger in Aero-acoustic Wind Tunnel

Abstract:

Rectangular steel finned elliptical tube heat exchanger with low pressure loss and good heat transfer performance is used at Aero-acoustic Wind Tunnel. In order to estimate the acoustic performance of the heat exchanger, microphones are used to test the acoustic performance of the heat exchanger inlet and outlet at a model wind tunnel in the present study. The test results show that the difference of total sound pressure level between heat exchanger inlet and outlet is almost 8.9~10.7dB at five test velocities, and the frequency of aero-noise generated by heat exchanger is mainly in the low and middle frequency range. Further discussion shows that with increasing in the upstream flow velocity, the frequency of shedding vortex increases linearly, suggesting the existence of a constant Strouhal number for a given heat exchanger.