VISCOSITY MEASUREMENT OF LIQUIDS IN PIPE FLOW BY FORCED LONGITUDINAL VIBRATIONS IN THE PIPE WALL ON A FINITE LENGTH

1992 ◽  
pp. 899-901
Author(s):  
TH. BROKATE ◽  
TH. GAST
Keyword(s):  
Finite Length ◽  
Pipe Flow ◽  
Pipe Wall ◽  
Viscosity Measurement ◽  
Longitudinal Vibrations

scholarly journals Perspective on the Response of Turbulent Pipe Flows to Strong Perturbations

Fluids ◽  
2021 ◽  
Vol 6 (6) ◽  
pp. 208
Author(s):  
Liuyang Ding ◽  
Tyler Van Buren ◽  
Ian E. Gunady ◽  
Alexander J. Smits
Keyword(s):  
Pipe Flow ◽  
Abrupt Change ◽  
Pipe Wall ◽  
Surface Condition ◽  
Initial Response ◽  
Body Of Revolution ◽  
Future Directions ◽  
Pipe Flows ◽  
Roughness Elements ◽  
Pipe Geometry

Pipe flow responds to strong perturbations in ways that are fundamentally different from the response exhibited by boundary layers undergoing a similar perturbation, primarily because of the confinement offered by the pipe wall, and the need to satisfy continuity. We review such differences by examining previous literature, with a particular focus on the response of pipe flow to three different kinds of disturbances: the abrupt change in surface condition from rough to smooth, the obstruction due to presence of a single square bar roughness elements of different sizes, and the flow downstream of a streamlined body-of-revolution placed on the centerline of the pipe. In each case, the initial response is strongly influenced by the pipe geometry, but far downstream all three flows display a common feature, which is the very slow, second-order recovery that can be explained using a model based on the Reynolds stress equations. Some future directions for research are also given.

scholarly journals Boundary Layer Control by Means of Strong Injection

1984 ◽  
Vol 51 (1) ◽  
pp. 27-34 ◽  
Author(s):  
R.-J. Yang ◽  
M. Holt
Keyword(s):  
Pipe Flow ◽  
Pipe Wall ◽  
Flow System ◽  
Wall Jet ◽  
Direction Parallel ◽  
Coal Gas ◽  
Coal Gasifier ◽  
Gas Products ◽  
Strong Injection ◽  
Layer Control

The gas mixture produced by coal gasifier contains components that have serious corrosive effects on the walls of the pipe flow system. To reduce these, a non-corrosive gas is injected into the stream of the coal gas products, in a direction parallel to the pipe wall. The interaction between the injected stream and the original pipe flow is investigated analytically and is an example of the so-called Wall Jet Problem.

scholarly journals Impact of Main Pipe Flow Velocity on Leakage and Intrusion Flow: An Experimental Study

Water ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 118 ◽  
Author(s):  
Yu Shao ◽  
Tian Yao ◽  
Jinzhe Gong ◽  
Jinjie Liu ◽  
Tuqiao Zhang ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Pipe Flow ◽  
Pressure Difference ◽  
Discharge Coefficient ◽  
Pipe Wall ◽  
Technical Note ◽  
Opposite Pattern ◽  
Main Pipe ◽  
Pressurized Pipelines ◽  
The Impact

The classic orifice equation is commonly used to calculate the leakage and intrusion rate for pressurized pipelines with cracks on the pipe wall. The conventional orifice equation does not consider the effect of the flow velocity in the main pipe, and there is a lack of studies on this matter. For this technical note, the influence of the main pipe flow velocity on the outflow and inflow through a crack on the pipe wall was studied in the laboratory. The experimental results show that the impact of the main pipe flow velocity can be significant. When the pressure difference across the orifice was constant, with the increase of the main pipe flow velocity, the outflow velocity increased, but the contraction area of the jet and the outflow discharge coefficient decreased. By comparing orifices with different shapes, it was found that the discharge from the circumferential crack was most sensitive to the main pipe flow velocity. In addition, the main pipe flow promoted the orifice inflow. When the pressure difference across the orifice was constant, with the increase of the main pipe flow velocity, the inflow discharge coefficient increased, which is the opposite pattern to that of the orifice outflow.

Receptivity of pipe Poiseuille flow

1996 ◽  
Vol 315 ◽  
pp. 119-137 ◽  
Author(s):  
Anatoli Tumin
Keyword(s):  
Collocation Method ◽  
Poiseuille Flow ◽  
Chebyshev Polynomials ◽  
Pipe Flow ◽  
Pipe Wall ◽  
Numerical Procedure ◽  
Amplitude Distribution ◽  
Narrow Gap ◽  
Method Of Solution ◽  
Similar Character

The receptivity problem is considered for pipe flow with periodic blow–suction through a narrow gap in the pipe wall. Axisymmetric and non-axisymmetric modes (1, 2, and 3) are analysed. The method of solution is based on global eigenvalue analysis for spatially growing disturbances in circular pipe Poiseuille flow. The numerical procedure is formulated in terms of the collocation method with the Chebyshev polynomials application. The receptivity problem is solved with an expansion of the solution in a biorthogonal eigenfunction system, and it was found that there is an excitation of many eigenmodes, which should be taken into account. The result explains the non-similar character of the amplitude distribution in the downstream direction that was observed in experiments.

The Effect of Blade Manipulator in Fully Developed Pipe Flow

1992 ◽  
Vol 114 (4) ◽  
pp. 687-689 ◽  
Author(s):  
Y. A. Mah ◽  
B. C. Khoo ◽  
Y. T. Chew
Keyword(s):  
Boundary Layer ◽  
Pipe Flow ◽  
Pipe Wall ◽  
Stress Measurement ◽  
Volumetric Flow Rate ◽  
Rate Measurement ◽  
Flow Rate Measurement ◽  
Equivalent Boundary ◽  
Layer Flow ◽  
Wall Shear Stress Measurement

Experiments were carried out in applying the concept of passive device called BLADEs (boundary-layer alteration devices) to fully developed pipe flow to assess its feasibility as a drag reduction device. The results of both the volumetric flow rate measurement and the pipe wall pressure distribution taken far downstream show that there is a net increase in drag with the device. With BLADES in tandem arrangement, there is a further net increase in drag which is contrary to its counterpart in boundary layer flow. Although the wall shear stress measurement following the device indicates some reduction in local drag, its magnitude of reduction is much smaller than that seen in the equivalent boundary flow. All these results suggest little possibility of any useful application of BLADEs to pipe flow.

scholarly journals The stability of developing pipe flow at high Reynolds number and the existence of nonlinear neutral centre modes

2011 ◽  
Vol 684 ◽  
pp. 284-315 ◽  
Author(s):  
Andrew G. Walton
Keyword(s):  
Reynolds Number ◽  
Pipe Flow ◽  
High Reynolds Number ◽  
Pipe Wall ◽  
Fluid Velocity ◽  
Nonlinear Effects ◽  
Neutral Curve ◽  
High Reynolds ◽  
The Stability ◽  
Axisymmetric Disturbances

AbstractThe high-Reynolds-number stability of unsteady pipe flow to axisymmetric disturbances is studied using asymptotic analysis. It is shown that as the disturbance amplitude is increased, nonlinear effects first become significant within the critical layer, which moves away from the pipe wall as a result. It is found that the flow stabilizes once the basic profile has become sufficiently fully developed. By tracing the nonlinear neutral curve back to earlier times, it is found that in addition to the wall mode, which arises from a classical upper branch linear stability analysis, there also exists a nonlinear neutral centre mode, governed primarily by inviscid dynamics. The centre mode problem is solved numerically and the results show the existence of a concentrated region of vorticity centred on or close to the pipe axis and propagating downstream at almost the maximum fluid velocity. The connection between this structure and the puffs and slugs of vorticity observed in experiments is discussed.

scholarly journals Ultrasonic Measurement for the Experimental Investigation of Velocity Distribution in Vapor-Liquid Boiling Bubbly Flow

2021 ◽  
Vol 12 (1) ◽  
pp. 16-28
Author(s):  
Wongsakorn Wongsaroj ◽  
Hideharu Takahashi ◽  
Natee Thong-Un ◽  
Hiroshige Kikura
Keyword(s):  
Velocity Distribution ◽  
Pipe Flow ◽  
Pipe Wall ◽  
Bubbly Flow ◽  
Ultrasonic Measurement ◽  
Subcooled Boiling ◽  
Vertical Pipe ◽  
Two Phase ◽  
Flow Apparatus ◽  
Vapor Liquid

This study proposes an ultrasonic velocity profiler (UVP) with a single ultrasonic gas-liquid two-phase separation (SUTS) technique to measure the velocity distribution of vapor-liquid boiling bubbly flow. The proposed technique is capable of measuring the velocity of the vapor bubble and liquid separately in boiling conditions. To confirm the viability of the measurement technique, the experiment is conducted on vertical pipe flow apparatus. The ultrasonic transmission and effect of ultrasonic refraction through the pipe wall and water are investigated at ambient temperature until subcooled boiling temperature is reached. The velocity profile in the water at elevated temperature is measured to verify the ability of the technique in this application. The bubbly flow velocity distribution measurement in boiling conditions is then demonstrated. The results show that the proposed technique can effectively investigate the velocity of both phases under various fluid conditions in boiling bubbly flow.

Incompresible Periodically Reversing Flow in a Conical Pipeline of Finite Length

2009 ◽  
Author(s):  
J. Luis Luviano-Ortiz ◽  
Eduardo Ramos ◽  
Abel Hernandez-Guerrero ◽  
Jose-Manuel Luna
Keyword(s):  
Finite Length ◽  
Pipe Flow ◽  
Oscillatory Flow ◽  
Flow Behavior ◽  
Three Dimensional ◽  
Diameter Ratio ◽  
Womersley Number ◽  
Hydrodynamic Behavior ◽  
Maximum Displacement ◽  
Generation Of Vortices

A numerical three-dimensional study has been carried out to analyze the hydrodynamic behavior of an incompressible periodically-reversing flow in a conical pipeline of finite length. In order to generate the oscillatory flow, a two pistons-driven pipe flow was established (the pistons were placed at the ends of the pipeline.) In the smaller piston the Womersley number was set to 16 while the axial displacement/diameter ratio was set to 1. The hydrodynamic flow behavior is considered and discussed for the accelerating and decelerating phases of the cycle. The numerical results show the generation of vortices for different penetration lengths. One of the most representative results is that in the position of 183.25°, after the pistons reach their maximum displacement, the flow pattern loses the axial symmetry that had appeared for previous phases of the cycle.

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