Effect of sound excitation on the flow field and convection heat transfer around a cylinder

The combination of experiment and numerical simulation, sound frequency and sound pressure level on the flow field, and heat transfer around a cylinder with two flow patterns are investigated. Flow patterns are periodic laminar flow (L3, Re0 = 100) and wake transition (TrW2, Re0 = 300), respectively. Sound frequency range f = 100-1000 Hz, and sound pressure level range SPL = 127-145 dB. Based on the influence of acoustic charac-teristics on the viscous boundary layer and thermal boundary layer of cylindrical wall, constructed a functional relationship between convection heat transfer and sound wave frequency and sound pressure level. Influenced by the acoustic action, the flow field force around the cylinder, the vortex street structure, the vortex size, and the length of the wake area may be changed. Acoustic action flow field excitation fluid particle velocity amplitude increased. As the sound pressure level increased, the amplitude of the fluid mass vibration velocity increased. From the experimental results, it can be seen that for the acoustic frequency effect, the heat transfer coefficient increases with increasing sound frequency. For the particle velocity amplitude effect, as the acoustic Reynolds number increases, the heat transfer coefficient increases and is 2.3 times higher than that without acoustic disturbance in the wake turning flow regime. In comparison with numerical and experimental results, the error is less than 15%, which meets the actual requirements of the project. It has been shown that sound waves can enhance the convective heat transfer around a cylinder in the cross-flow.