Heat Transfer Engineering, Vol.33, No.11, 972-981, 2012
Experimental and Numerical Study of Flow and Heat Transfer in Trapezoidal Microchannels
An experimental investigation has been performed on the laminar flow and heat transfer of water in trapezoidal silicon microchannels. Two three-dimensional (3D) heat transfer models have been developed to simulate the heat transfer performance under the same experimental conditions. Due to the sudden contraction, the velocity develops a little faster, which makes the pressure drop slightly lower than that of the neglected entrance and exit plenum regions. Due to the heat conduction in the lateral parts of wafer, the maximum temperature appears near the outlet of microchannel and the temperature is slightly different among the microchannels. Nearer to the lateral parts of wafer, the the temperature reaches the maximum for the sidewall later. With a given pumping power, the thermal resistance decreases as increase of the heating power at the substrate. However, the subthermal resistance proportion is nearly unchanged. With an increase of pumping power, the subthermal resistance proportion of convection increases rapidly at first, then gradually approaches an asymptote.