Abstract
In general, fluctuating flow with a temperature difference causes a wall-temperature fluctuation due to the unsteady heat transfer. This effect called "unsteady conjugate heat transfer" leads to more or less an erroneous prediction of total amount of heat transfer due to the nonlinear relationship. In order to provide quantitative information on this, we tried to model the temporal fluctuation of the heat transfer coefficient caused by flow turbulence on the basis of the measured data obtained using high-speed infrared thermography. This model seems to be available to predict the conjugate effect easily by applying it as a boundary condition of a simple heat conduction simulation inside a solid wall.