Effect of orientation on the convective boiling performance of microchannel heat sink using HFE-7100

The present study investigates the heat transfer and pressure drop characteristics of the dielectric fluid HFE-7100 within multiport microrchannel heat sink with square microchannels having a hydraulic diameter of 790 µm subject to a tilted arrangement of 45 degree. For a mass flux of 100 or 200 kg/m
²
·s, it is found that the heat transfer coefficients are for the tilted arrangement is roughly the same with the horizontal arrangement. In the meantime, the corresponding heat transfer coefficients rises slightly with the vapor quality. The pressure drop amid tilted arrangement and horizontal one is also small for a mass flux of 200 kg/m
²
·s. However, for a smaller mass flux of 100 kg/m
²
·s, the pressure drop for tilted arrangement is slightly higher than that of horizontal one.