Effect of Sound Field on the Forced Convection Heat Transfer from an Isothermal Cylinder

음장이 등온원통으로부터의 강제대류 열전달에 미치는 영향

The effect of sound on the heat transfer from an isothermal cylinder in cross flow is investigated by numerical analysis. The modeling is made for the laminar incompressible flow fluctuating in the range of the Reynolds number, 5.leq.Re.leq.35, by the sinusoidal acoustic field. The instantaneous response of the flow and heat transfer is simulated for various frequencies. It is shown that the heat transfer amplitude decreases and the phase lags behind the flow velocity with increase in the frequency. The time-mean effects of the acoustic field on the flow field and heat transfer, known as the acoustic and thermoacoustic streaming, are analyzed. The time-mean heat transfer coefficients are decreased around the forward stagnation point but increased in the wake region. Such a local difference in heat transfer coefficients is a function of the frequency and becomes greatest at some frequency. However, with balance between the local increase and decrease, the overall heat transfer coefficient is almost unaffected by sound.

본 연구의 목적은 음장의 입자속도가 기류의 평균속도와 비슷한 크기인 경우에 원통으로부터 열전달의 동특성과 한 사이클의 평균값인 평균열전달이 음장에 의하여 어떠한 영향을 받는가를 구하기 위한 것이다.