Heat transfer enhancement by pulsating flow in a triangular grooved channel has been experimentally investigated. Effects of Reynolds number Re, Strouhal number St, pulsation amplitude A on the heat transfer enhancement were studied. The experimental results show that, the pulsating flow can significantly enhance heat transfer compared to the steady flow case, for instance, an enhancement of 115% is achieved at Re=400, A=0.5 and St=0.3. There exists an optimal Strouhal number corresponding to the maximum heat transfer enhancement factor. The heat transfer enhancement factor increases with the increase of Reynolds number and pulsation amplitude.

In this paper, the heat transfer enhancement by pulsating laminar flow in rectangular grooved channels was experimentally investigated. Effects of Reynolds number Re, pulsation frequency, groove depth and groove length on the heat transfer enhancement were studied. Experimental results show that Nusselt number increases with Re increases both in steady and pulsating flow cases. Pulsating flow can efficiently enhance heat transfer in the grooved channels and the heat transfer enhancement factor increases with the increase of Re. There exists an optimal pulsation frequency, corresponding to the maximum heat transfer enhancement factor, which is almost the same for different Re, groove depth and groove length.