Numerical investigations of flow behavior and enhancement of heat transfer of two-phase flow (water-air) in two-pass channel with various shapes of perforated area of curved ribs.

In this paper investigation numerically varies shape perforated area on enhancement in heat transfer was investigated along two-pass ribbed channel with internally of two-phase flow. Ribs have a curved shape with two cases. In this paper investigation numerically the effects of shape perforated area on enhancement in heat transfer was investigated along two-pass ribbed channel with internally of two-phase flow. Ribs have a curved shape with two cams with perforated same areas with various shapes; triangle, square, circle areas and comparison with solid case. The study performed at same conditions for all cases, of water & air velocities are (0.1684m/s) & (2.193m/s), respectively. Numerical simulation by ANSYS FLUENT 2021 R1 employed to study the heat transfer enhancement. The results showed that the circle area have high turbulence to increase enhancing in heat transfer coefficients in compared with other cases. However, the pressure decreased with ratio of passing from inlet to outlet ribbed region through bend region (S) to Hydraulic diameter (D) in ribbed region but in bend region a sharply in triangle and square cases decreased in pressure lead to increase pressure drop and increased losses. The percentage of enhancing heat convective was around (25% in case of square perforated area, 29% in triangle perforated area, 35% in circle perforated area) in comparison with solid curved ribs. [ABSTRACT FROM AUTHOR]