Abstract
Fluid temperature fluctuation of low frequency, known as the thermal striping phenomena, occurs in the mixing tees of nuclear components with hot and cold fluids. In this study, in order to elucidate the heat transfer characteristic of the thermal striping phenomena, fluid temperature fluctuation is developed by the periodic large scale vortices in a channel flow with rectangular cylinder, and the heat transfer coefficients were measured by the thin film heat flux sensor which was installed in the channel wall. The fluctuations of Nusselt number and fluid temperature are antiphase in the periodic temperature fluctuation field. And the time averaged Nusselt number in the fluid temperature fluctuation field is almost equal to that of the constant fluid temperature, although the R. M. S. of Nusselt number increases with fluid temperature fluctuation.
