scholarly journals Analysis on a Snow-Water Mixture Flow in a Horizontal Pipe by Three-Layer Model

1989 ◽  
Vol 5 (4) ◽  
pp. 3-15
Author(s):  
HIROSHI TAKAHASHI ◽  
MIKIO SASAKI ◽  
TOSHIO KAWASHIMA
Keyword(s):  
Water Mixture ◽  
Layer Model ◽  
Mixture Flow ◽  
Horizontal Pipe ◽  
Snow Water

scholarly journals Experimental investigation of coarse particles-water mixture flow in horizontal and inclined pipes

2014 ◽  
Vol 62 (3) ◽  
pp. 241-247 ◽  
Author(s):  
Pavel Vlasák ◽  
Zdeněk Chára ◽  
Jan Krupička ◽  
Jiří Konfršt
Keyword(s):  
Dominant Mode ◽  
Solid Particles ◽  
Coarse Grained ◽  
Water Mixture ◽  
Mixture Flow ◽  
Horizontal Pipe ◽  
Pressure Drops ◽  
Steel Pipes ◽  
Inner Diameter ◽  
Inclined Pipes

Abstract The effect of solid concentration and mixture velocity on the flow behaviour, pressure drops, and concentration distribution of coarse particle-water mixtures in horizontal, vertical, and inclined smooth stainless steel pipes of inner diameter D = 100 mm was experimentally investigated. Graded basalt pebbles were used as solid particles. The study revealed that the coarse-grained particle-water mixtures in the horizontal and inclined pipes were significantly stratified. The solid particles moved principally in a layer close to the pipe invert; however for higher and moderate flow velocities, particle saltation became the dominant mode of particle conveyance. Frictional pressure drops in the horizontal pipe were found to be markedly higher than in the vertical pipe, while the frictional pressure drops in the ascending pipe increased with inclination angle up to about 30°.

Energy Loss in Snow-Water Mixture Flow

2003 ◽  
Author(s):  
Mikio Sasaki ◽  
Takahiro Takeuchi ◽  
Hiroshi Takahashi
Keyword(s):  
Specific Gravity ◽  
Energy Loss ◽  
Friction Factor ◽  
Pure Water ◽  
Solid Particles ◽  
Water Mixture ◽  
Solid Concentration ◽  
Mixture Flow ◽  
Snow Water ◽  
Relative Friction

Energy losses in the solid-water mixture flow where the density of solid is nearly equal to that of fluid were observed in horizontal pipelines. The observation was carried out to investigate the influence that the specific gravity of the solid particles exerted on the energy loss. A relative friction factor based on the friction factor of the pure water flow becomes larger as the solid concentration increases in the mixture flow of solid particles with the specific gravity 0.86 and 1.04. The relative friction factor is given with the Froude number, the solid concentration and the specific gravity of solid.

scholarly journals Measurement of the Snow Fraction in a Snow/water Mixture Flow in a Pipe

1986 ◽  
Vol 29 (253) ◽  
pp. 2156-2160
Author(s):  
Masataka SHIRAKASHI ◽  
Atsushi KOSHIO ◽  
Shoichi WAKlYA
Keyword(s):  
Water Mixture ◽  
Mixture Flow ◽  
Snow Water

scholarly journals Measurement of the snow fraction in a snow/water mixture flow in a pipe.

1985 ◽  
Vol 51 (471) ◽  
pp. 3782-3785
Author(s):  
Masataka SHIRAKASHI ◽  
Atsushi KOSHIO ◽  
Shoichi WAKIYA
Keyword(s):  
Water Mixture ◽  
Mixture Flow ◽  
Snow Water

CFD Simulations of Oil-Water Flow Behavior in Horizontal Pipe Separator

2019 ◽  
Author(s):  
Srinivas Swaroop Kolla ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Flow Behavior ◽  
Scale Up ◽  
Water Mixture ◽  
Hexahedral Mesh ◽  
Cfd Simulations ◽  
Mixture Flow ◽  
Horizontal Pipe ◽  
Vof Model ◽  
Oil Water ◽  
Grid Convergence Index

Abstract Horizontal Pipe Separators (HPS©) are used for separation of oil and water especially in subsea environment owing to its simplicity, installation, and operation. In the present work, the flow phenomena in the HPS with 0.0762m ID and 10.3 m long separating oil and water with specific gravities of 1 and 0.857 is simulated and analyzed using ANSYS Fluent 16. Hexahedral mesh with boundary layers has been done utilizing ANSYS design modeler for this analysis. A grid independence study is performed on 3 different mesh grids using grid convergence index. 3-D simulations are carried out using a Hybrid Eulerian-Eulerian Multifluid VOF model for watercuts ranging from 20 to 80% and a mixture velocity of 0.08 m/s. The CFD simulations analyzed the effect of watercut on the oil-water mixture flow behavior and the entry region required for the oil and water to separate in the HPS. These simulation results are validated against acquired experimental data by Othman in 2010. These simulations provide an insight to understand the effects of diameter, watercut, and mixture velocities on the performance of HPS to aid in its design and scale up/down studies.

Optimum air-demand ratio for maximum aeration efficiency in high-head gated circular conduits

2014 ◽  
Vol 70 (5) ◽  
pp. 871-877 ◽  
Author(s):  
Fahri Ozkan ◽  
M. Cihat Tuna ◽  
Ahmet Baylar ◽  
Mualla Ozturk
Keyword(s):  
Froude Number ◽  
High Speed ◽  
Water Mixture ◽  
High Speed Flow ◽  
Mixture Flow ◽  
Speed Flow ◽  
Aeration Efficiency ◽  
High Head ◽  
Closed Conduit ◽  
Air Vent

Oxygen is an important component of water quality and its ability to sustain life. Water aeration is the process of introducing air into a body of water to increase its oxygen saturation. Water aeration can be accomplished in a variety of ways, for instance, closed-conduit aeration. High-speed flow in a closed conduit involves air-water mixture flow. The air flow results from the subatmospheric pressure downstream of the gate. The air entrained by the high-speed flow is supplied by the air vent. The air entrained into the flow in the form of a large number of bubbles accelerates oxygen transfer and hence also increases aeration efficiency. In the present work, the optimum air-demand ratio for maximum aeration efficiency in high-head gated circular conduits was studied experimentally. Results showed that aeration efficiency increased with the air-demand ratio to a certain point and then aeration efficiency did not change with a further increase of the air-demand ratio. Thus, there was an optimum value for the air-demand ratio, depending on the Froude number, which provides maximum aeration efficiency. Furthermore, a design formula for aeration efficiency was presented relating aeration efficiency to the air-demand ratio and Froude number.

Heat Transfer Correlations for Air-Water Two-Phase Flow of Different Flow Patterns in a Horizontal Pipe

2000 ◽  
Author(s):  
Dongwoo Kim ◽  
Jae-yong Kim ◽  
Afshin J. Ghajar ◽  
Ronald L. Dougherty
Keyword(s):  
Heat Transfer ◽  
Flow Patterns ◽  
Mean Deviation ◽  
Water Mixture ◽  
Two Phase ◽  
Horizontal Pipe ◽  
Flux Boundary Condition ◽  
Uniform Wall ◽  
Heat Transfer Correlations ◽  
Two Phase Heat Transfer

Abstract New heat transfer correlations were developed for two-phase heat transfer in a horizontal pipe for different flow patterns. Flow patterns were observed in a transparent circular pipe (2.54 cm I.D. and L/D = 96) using an air/water mixture. Visual identification of the flow patterns was supplemented with photographic data, and the results were plotted on the flow regime map proposed by Taitel and Dukler and agreed quite well with each other. A two-phase heat transfer experimental setup was built for this study and a total of 150 two-phase heat transfer data with different flow patterns were obtained under a uniform wall heat flux boundary condition. For these data, the superficial Reynolds number ranged from 640 to 35,500 for the liquid and from 540 to 21,200 for the gas. Our previously developed robust two-phase heat transfer correlation for a vertical with modified constants predicted the horizontal pipe air-water heat transfer experimental data with good accuracy. Overall the proposed correlations predicted the data with a mean deviation of 1.0% and an rms deviation of 12%.

Sign in / Sign up

Export Citation Format

Share Document