Numerical simulation of heat transfer of two-phase flow in mini-channel heat sink and investigation the effect of pin-fin shape on flow maldistribution

Nowadays, given the rising power of processors and the increase in operating temperature of these objects, the cooling and heat loss process is necessary to prevent the breakdown of these devices. Considering the ability to dissipate high heat flux in mini-channels and low pressure drop, in this study, the performance of mini-channels with different inlet headers was studied. Accordingly, 3 pin fins with elliptical, circular and V-shaped cross-sections in the inlet header were examined in terms of velocity distribution uniformity and heat sink surface temperature reduction. The lowest maldistribution and surface temperature were obtained for the header with elliptical pin fins having a diameter ratio of a/b = 2. Also, the effect of employing the nanofluid in mini-channel on pressure drop and heat transfer was investigated by utilizing the two-phase mixture model. The results showed that with the rise of volume fraction ( null ) and Reynolds number (Re), thermal resistance was reduced significantly. Also, the highest Nusselt number (Nu) with the Re of 3000 and volume fraction of 0.5% was ob-tained to be equal to 77.3.