In the high flux test module of the International Fusion Materials Irradiation Facility, temperature control of irradiated specimens are done by gas cooling and electric heating. The width of cooling channels is supposed to be 1 mm in the module vessel which is a rectangular duct with wall thickness of 1 mm. Since there is large pressure difference up to several atmospheric pressure between the inside and outside the vessel, it is considered that the vessel wall and the cooling channels easily deforms. In order to estimate cooling performances for the coolant flowing in the deformed channel, we conduct a finite element analysis of turbulent heat transfer in a mildly curved channel using large-eddy simulation. It is found from the simulation that heat transfer on the concave wall drastically changes according to local change in flow aspect such as separation while that on the opposite flat wall is affected only by average flow velocity and is not largely changed by the channel deformation.
