Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Turbulent Flow in a Porous Tube with Wall Suction
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Turbulent Flow in a Porous Tube with Wall Suction
Author: Manouchehr Heidarpour
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
This study examines the effects of suction (i.e. lateral flow through the walls) on the structure of a fully developed turbulent pipe flow. Also the effect of suction on pressure gradient and pressure change is examined experimentally. The frictional characteristics of Irrigro$\sp{\circler,}$ the porous tubing used in this investigation, is studied by means of a comprehensive experimental program that considered different lengths of porous tubing. Three aspects of flow in porous pipes are investigated in this study, (i) a computational study of the effects of suction on the flow characteristics, (ii) an experimental study of the frictional characteristics of the porous tubing with no suction condition and (iii) an experimental study of pressure change along a porous tubing with lateral flow. The numerical study of turbulent pipe flow with wall suction rates ranging from A = 0 to 13 percent showed that in fully developed pipe flow, wall suction results in a more uniform velocity distribution with increased near-wall velocity values and reduced velocities near the centerline. The near-wall component of radial velocity, $\nu,$ increases with increasing distance from the wall in the zone near the pipe wall. The absolute levels of turbulent kinetic energy decrease with increasing suction rate. Wall suction increases the wall shear stress, $\tau\sb{\rm w},$ along the wall of the tube. The increase in $\tau\sb{\rm w}$ is significant even for the smallest suction rate (up to 30 percent) while such an increase is much higher for A = 13 percent (up to 360 percent). Analysis of the experimental friction loss data obtained for small diameter porous tubing in this study confirmed that the Colebrook and White (C-W) equation is a very accurate predictor of the friction factor for porous tubing with small diameter size and Reynolds numbers less than 100,000. These results are in agreement with the results of Aggarwal et al (1972). The value of the relative roughness obtained in this study showed that the porous tubing under study is smoother than most of the tubing used as laterals in the traditional trickle irrigation. Also, the fact that the friction factors agreed with the Colebrook-White law indicates that the physical roughness in the porous tubing under study corresponds very nearly to the equivalent sand roughness with a relative roughness of about e/D = 0.002. A relationship was established as a convenient and accurate head loss prediction equation (within 5% error) by combining a power function with the Darcy-Weisbach equation. The combination equation is correctable for viscosity changes and accurate for the porous pipe tubing under study. A pressure change and a pressure gradient prediction relationship were established in the transition zone of the Moody diagram for high suction rates, assuming a uniform radial flow rate along the suction region. The relationships presented herein are based on a control volume approach analysis and incorporated the data obtained from laboratory studies on the porous tubing under study.
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
This study examines the effects of suction (i.e. lateral flow through the walls) on the structure of a fully developed turbulent pipe flow. Also the effect of suction on pressure gradient and pressure change is examined experimentally. The frictional characteristics of Irrigro$\sp{\circler,}$ the porous tubing used in this investigation, is studied by means of a comprehensive experimental program that considered different lengths of porous tubing. Three aspects of flow in porous pipes are investigated in this study, (i) a computational study of the effects of suction on the flow characteristics, (ii) an experimental study of the frictional characteristics of the porous tubing with no suction condition and (iii) an experimental study of pressure change along a porous tubing with lateral flow. The numerical study of turbulent pipe flow with wall suction rates ranging from A = 0 to 13 percent showed that in fully developed pipe flow, wall suction results in a more uniform velocity distribution with increased near-wall velocity values and reduced velocities near the centerline. The near-wall component of radial velocity, $\nu,$ increases with increasing distance from the wall in the zone near the pipe wall. The absolute levels of turbulent kinetic energy decrease with increasing suction rate. Wall suction increases the wall shear stress, $\tau\sb{\rm w},$ along the wall of the tube. The increase in $\tau\sb{\rm w}$ is significant even for the smallest suction rate (up to 30 percent) while such an increase is much higher for A = 13 percent (up to 360 percent). Analysis of the experimental friction loss data obtained for small diameter porous tubing in this study confirmed that the Colebrook and White (C-W) equation is a very accurate predictor of the friction factor for porous tubing with small diameter size and Reynolds numbers less than 100,000. These results are in agreement with the results of Aggarwal et al (1972). The value of the relative roughness obtained in this study showed that the porous tubing under study is smoother than most of the tubing used as laterals in the traditional trickle irrigation. Also, the fact that the friction factors agreed with the Colebrook-White law indicates that the physical roughness in the porous tubing under study corresponds very nearly to the equivalent sand roughness with a relative roughness of about e/D = 0.002. A relationship was established as a convenient and accurate head loss prediction equation (within 5% error) by combining a power function with the Darcy-Weisbach equation. The combination equation is correctable for viscosity changes and accurate for the porous pipe tubing under study. A pressure change and a pressure gradient prediction relationship were established in the transition zone of the Moody diagram for high suction rates, assuming a uniform radial flow rate along the suction region. The relationships presented herein are based on a control volume approach analysis and incorporated the data obtained from laboratory studies on the porous tubing under study.
Velocity and Pressure Distributions in Turbulent Pipe Flow with Uniform Wall Suction
Author: Harold L. Weissberg
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 250
Book Description
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 250
Book Description
On Turbulent Flow in a Tube with Wall Suction
Author: A. Brosh
Publisher:
ISBN:
Category :
Languages : en
Pages : 28
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 28
Book Description
Turbulent Flow in a Tube with Wall Suction
Author: Lee Merkine
Publisher:
ISBN:
Category :
Languages : en
Pages : 20
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 20
Book Description
Experimental Study of Turbulent Flow in a Tube with Wall Suction
Author: A. Brosh
Publisher:
ISBN:
Category :
Languages : en
Pages : 46
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 46
Book Description
Applied Mechanics Reviews
Author:
Publisher:
ISBN:
Category : Mechanics, Applied
Languages : en
Pages : 628
Book Description
Publisher:
ISBN:
Category : Mechanics, Applied
Languages : en
Pages : 628
Book Description
ASME 65-APM-29
Author: Reuben M. Olson
Publisher:
ISBN:
Category : Speed
Languages : en
Pages : 11
Book Description
Publisher:
ISBN:
Category : Speed
Languages : en
Pages : 11
Book Description
ASME 69-HT-57
Author: Wolfgang Rodi
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 9
Book Description
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 9
Book Description
Turbulent Flows and Heat Transfer
Author: Chia-Ch'iao Lin
Publisher: Princeton University Press
ISBN: 1400879418
Category : Science
Languages : en
Pages : 570
Book Description
Volume V of the High Speed Aerodynamics and Jet Propulsion series. Topics include transition from laminar to turbulent flow; turbulent flow; statistical theories of turbulence; conduction of heat; convective heat transfer and friction in flow of liquids; convective heat transfer in gases; cooling by protective fluid films; physical basis of thermal radiation; and engineering calculations of radiant heat exchange. Originally published in 1959. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.
Publisher: Princeton University Press
ISBN: 1400879418
Category : Science
Languages : en
Pages : 570
Book Description
Volume V of the High Speed Aerodynamics and Jet Propulsion series. Topics include transition from laminar to turbulent flow; turbulent flow; statistical theories of turbulence; conduction of heat; convective heat transfer and friction in flow of liquids; convective heat transfer in gases; cooling by protective fluid films; physical basis of thermal radiation; and engineering calculations of radiant heat exchange. Originally published in 1959. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.