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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]

This research has cared about studying the effect of vibration obtained by the rotor blade row of the turbine on the aerodynamics flow between the turbine blades. The research focuses on studying the pressure distribution and velocity profile between blades turbine with effect force vibration for a different frequency (3-33 Hz). By this study, the effect of vibration on the gas turbine performance. An experimental rig was created at the University of Babylon University /Iraq by the authors. The cascade blades examined in this work are a real part that is mainly collected from Hilla/Iraq gas turbine power station. The distribution pressure is examined by sensor pressure at 18 in the region of the blade and is divided into two groups the first group on the suction side of the blade and the second on the pressure side. The pressure in X-positions was calculated with a different frequency for the blade. In the middle of the chord, at the suction and pressure sides of the blade, compared to the numerical simulation, the experimental results show that there is an increase of 5%, a decrease of 6%, and an increase of 6% at level 6,21, and 36 mm, respectively, from the base. In addition, the increase in frequency leads to an increase in the pressure on the pressure and suction sides. The pressure distribution on both sides of the blade is affected by the shape of each blade section. Three sections of the blade are taken at different heights. [ABSTRACT FROM AUTHOR]