ملخص: An experimental setup has been built to examine the thermal response of a water turbulent forced convection between two parallel plates subjected to a periodic inlet temperature. In practice, a rectangular duct which a cross sectional area of (300 x 20 mm2) is constructed with stainless steel plates of 5 mm thickness. The experimental results (amplitude and phase lag along the channel) are compared with the elementary quasi-steady approach which employs a classical heat transfer coefficient at interface liquid-solid and also with an usual turbulent model which introduces the thermal eddy diffusivity and the velocity profiles. A boundary condition accounts for the effects of external convection, wall thermal capacitance and transverse heat conduction in the thick wall are considered. It is concluded that, for the smaller values of inlet frequency, the quasi-steady approach is able to predict the temperature behaviour inside the channel, but for higher frequencies (>0.05 Hz), this model becomes inadequate.

لغة: إنجليزية