An experimental study of two-phase pressure drop of acetone in triangular silicon micro-channels

Two-phase pressure drop was measured across a silicon micro-channels heat sink. Ten triangular micro-channels were fabricated in a silicon substrate by the etching technique in a silicon substrate. Each micro-channel is 300 μm in width and 212 μm in depth, forming the hydraulic diameter of 155.4 μm. Experimental studies were performed with acetone as working fluid under the following conditions: inlet pressure of Pin = 1.3-1.6 bar, inlet temperature Tin = 23.0-39.1 °C, mass velocity of G = 65.52-289.61 kg/m2 s, outlet quality of xe,out = 0.38-superheat, and heat flux of q = 141.92-481.08 kW/m2. The frictional pressure drop during flow boiling is estimated using two models, namely the homogeneous model and the separated flow model. In addition, the measured pressure drops are compared with those from a few correlation models available for macro-scales and mini/micro-scales. A new correlation is developed based on the Chisholm constant B as a function of mass flux. It is found that the new correlation can be used to predict the present experimental data within a mean absolute error (MAE) of 12.56%.