ENHANCEMENT THE HEAT TRANSFER FOR TWO-PHASE FLOW THROUGH A RECTANGULAR RIBBED VERTICAL CHANNEL

Abstract

The heat transfer coefficient and temperature distribution of two phase flow (water, air)
in rectangular ribbed vertical channel was investigated experimentally and numerically in
this work for different values of water and air superficial velocities (0.0421, 0.0842, 0.1158,
0.1474 and 0.1684 m/s) and (1.0964, 1.425, 1.644, 1.864 and 2.193 m/s), respectively, at
constant heat flux (120 W). The distribution of temperature along the channel was
photographed using thermal camera and compared with images for the corresponding
contours which found numerically. The experimental results of heat transfer coefficient
compared with computational fluid dynamics model simulated by Ansys fluent 15.0. A
good agreement has been found between the experimental and numerical data, where the
percentage deviation between the experimental and the numerical results is (1% - 6% ). The
results showed that, the local heat transfer coefficient increased by adding ribs, it also
increased as the velocity of the flow increased.