Transient Behavior of the Velocity Profile in Channel Flow of a Langmuir Monolayer

Langmuir ◽  
2000 ◽  
Vol 16 (24) ◽  
pp. 9433-9438 ◽  
Author(s):  
Ani T. Ivanova ◽  
Daniel K. Schwartz
Keyword(s):  
Velocity Profile ◽  
Channel Flow ◽  
Transient Behavior ◽  
Langmuir Monolayer

Temperature and Flow Rate Dependence of the Velocity Profile during Channel Flow of a Langmuir Monolayer

Langmuir ◽  
1999 ◽  
Vol 15 (13) ◽  
pp. 4622-4624 ◽  
Author(s):  
Ani Ivanova ◽  
M. Levent Kurnaz ◽  
Daniel K. Schwartz
Keyword(s):  
Velocity Profile ◽  
Channel Flow ◽  
Flow Rate ◽  
Langmuir Monolayer ◽  
Rate Dependence

Hydraulics of steeppass fishways

1991 ◽  
Vol 18 (6) ◽  
pp. 1024-1032 ◽  
Author(s):  
N. Rajaratnam ◽  
C. Katopodis
Keyword(s):  
Experimental Study ◽  
Velocity Profile ◽  
Channel Flow ◽  
Flow Rate ◽  
Open Channel ◽  
Maximum Velocity ◽  
Open Channel Flow ◽  
Width Ratio ◽  
Hydraulic Design ◽  
Theoretical Considerations

This paper presents the results of an experimental study on the hydraulics of steeppass fishways. Using theoretical considerations and experimental observations, an expression has been developed that relates the flow rate, slope of the fishway, and depth of flow. It was also found that the characteristic (similarity) velocity profile found earlier, for smaller values of depth to width ratio,y0/b, with the maximum velocity near the bottom, changes to a rather symmetrical profile with the maximum velocity occurring somewhere near the mid-depth for larger values of y0/b. A correlation has also been found for the maximum velocity. This paper also includes some observations on the M-type backwater curves that would appear in the fishway when the tailwater depths exceed uniform flow depths. Key words: fishways, hydraulics, turbulent flow, open-channel flow, hydraulic design.

Flow resistance of ice-covered streams

1984 ◽  
Vol 11 (4) ◽  
pp. 815-823 ◽  
Author(s):  
S. P. Chee ◽  
M. R. I. Haggag
Keyword(s):  
Velocity Profile ◽  
Channel Flow ◽  
Flow Resistance ◽  
Ice Cover ◽  
Navier Stokes ◽  
Navier Stokes Equation ◽  
Cross Sectional ◽  
Roughness Elements ◽  
Mixing Length Theory ◽  
Good Agreement

This paper deals with the underlying theory of the hydraulics of channel flow with a buoyant boundary as an ice cover. It commences by developing the velocity distribution in two-dimensional covered channel flow using the Reynolds form of the Navier–Stokes equation in conjunction with the Prandtl – Von Karman mixing length theory. Central to the theory is the division of the channel into two subsections. From the developed velocity profile, the functional relationship for the division surface is obtained. Finally, the composite roughness of the channel is derived.Experimental verification of the developed theory was conducted in laboratory flumes. Seven cross-sectional shapes were utilized. Ice covers were simulated with polyethylene plastic pellets as well as floating plywood boards with roughness elements attached to the underside. Velocity profile and composite roughness measurements made in these flumes were in good agreement with the theoretical equations. The composite roughness relationship derived from the theory is very comprehensive, as it takes into account not only the varying rugosities of the channel and its floating boundary but also the shape of the cross section. Key words: composite roughness, ice cover, flow resistance, velocity profile, buoyant boundary, covered channel.

scholarly journals Resolvent analysis of turbulent channel flow with manipulated mean velocity profile

2020 ◽  
Vol 15 (3) ◽  
pp. JFST0014-JFST0014
Author(s):  
Riko UEKUSA ◽  
Aika KAWAGOE ◽  
Yusuke NABAE ◽  
Koji FUKAGATA
Keyword(s):  
Velocity Profile ◽  
Channel Flow ◽  
Turbulent Channel Flow ◽  
Mean Velocity

Stability of turbulent channel flow, with application to Malkus's theory

1967 ◽  
Vol 27 (2) ◽  
pp. 253-272 ◽  
Author(s):  
W. C. Reynolds ◽  
W. G. Tiederman
Keyword(s):  
Velocity Profile ◽  
Channel Flow ◽  
Stability Problem ◽  
Turbulent Channel Flow ◽  
Velocity Profiles ◽  
Neutral Stability ◽  
Mean Velocity ◽  
The Mean ◽  
Two Parameter ◽  
Good Agreement

The Orr-Sommerfeld stability problem has been studied for velocity profiles appropriate to turbulent channel flow. The intent was to provide an evaluation of Malkus's theory that the flow assumes a state of maximum dissipation, subject to certain constraints, one of which is that the mean velocity profile is marginally stable. Dissipation rates and neutral stability curves were obtained for a representative two-parameter family of velocity profiles. Those in agreement with experimental profiles were found to be stable; the marginally stable profile of greatest dissipation was not in good agreement with experiments. An explanation for the apparent success of Malkus's theory is offered.

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