No abstract

Two-phase flow behaviour and its flow patterns have a significant effect in many applications in industry. Oil-gas is one of the two-phase flow types that have many applications in petroleum and power stations. An oil-gas two-phase flow behaviour and flow patterns have been investigated in an inclined pipe using two different tomography sensors: Wire Mesh sensor (WMS) and Electrical Capacitance Tomography (ECT). A special experimental facility was designed and built to operate the tow-phase flow application in the inclined pipe with the various angle of inclination. A set of experimental data were collected using operating conditions which covered a two-phase flow range of superficial velocity of gas (Usl) from 0.05 to 0.52 m/s and superficial velocity of liquid (Usg) from 0.05 to 4.7 m/s at atmospheric pressure and room temperature. Three inclined angles to change the pipe’s inclination 45, 60, and 80-degree were applied in the experiments. The Comparison between the Wire Mesh Sensor (WMS) and Electrical Capacitance Tomography (ECT) was completed experimentally. The results revealed that there is a good agreement between the two sensors, however; the WMS had a higher frequency which was calculated 1000 frames per second compared with the ECT which worked at 200 frames per second.

The heat sink with vertically rectangular interrupted fins was investigated numerically in a natural convection field, with steady-state heat transfer. A numerical study has been conducted using ANSYS Fluent software (R16.1) in order to develop a 3-D numerical model.  The dimensions of the fins are (305 mm length, 100 mm width, 17 mm height, and 9.5 mm space between fins. The number of fins used on the surface is eight. In this study, the heat input was used as follows: 20, 40, 60, 80, 100, and 120 watts. This study focused on interrupted rectangular fins with a different arrangement and angle of the fins. Results show that the addition of interruption in fins in various arrangements will improve the thermal performance of the heat sink, and through the results, a better interruption rate as an equation can be obtained.

Basically, the durability of hydraulic structures is heavily influenced by concrete surface resistance against mechanical wear. Hydro-abrasion is the term used to describe deterioration of concrete surface inflicted by the continuous removal of surface material due to the effect of water-dragged solids. This type of cumulative damage for the surface of concrete may be seen in practically all hydraulic systems, in varying degrees of severity. Essentially, such hydro-abrasive concrete wear reduces the life span of the hydraulic structure, and as a result of the maintenance necessary, the facility's non-operation during the repair time increases costs. The impact employed by the flow inclination angle, density (sand concentration in water), and velocity were studied in this work. The three various angles (30°, 45°, and 60°) different densities (35 and 45 kg/m3), and different velocities of 600, 900, and 1200 rpm were numerically determined using the program of ANSYS and the discrete phase model (DPM) for simulating the fluid solids. According to the directed numerical simulation, the greatest rate of erosion was observed when the inclination angle of the flowing water was 60°, while the least value was obtained when the inclination angle of flow was 45°, in addition, the erosion rate increases as the density and velocity increases.

To a great extent, for hydraulic structures,the durabilityrelies upon the resistance that the concrete surface offers to mechanical wear. The surface damage caused by the process of uninterrupted material removal,induced by the impact of the water-borne solid particles, is termed hydro-abrasion. In nearly all hydraulic structures, this kind of progressive deterioration of the concrete surfaces is observed, in different intensities. Obviously, such hydro-abrasive concrete wearing normally results in areduction in the service life of the hydro-technical facility, and consequently because of the repairs required, thenon-functioning of the facility during the repair period results in an expenditurespike. The influence exerted by the flow inclination angle was determined in this study. Numerical estimations were made of the four different angles (30°, 45°, 60°and 90°) employing the ANSYS software and discret phase model (DPM) to simulate the fluid particles. From the findings of numerical investigations, it was clear that the maximum erosion rate can be reached when the flow inclination angle is 45° while the lowest rate can be achieved at a flow inclinationangle of 30°.