Streamwise evolution of drag reduced turbulent boundary layer with polymer solutions

2020 ◽  
Vol 32 (6) ◽  
pp. 065108 ◽  
Author(s):  
Y. Shah ◽  
S. Yarusevych
Keyword(s):  
Boundary Layer ◽  
Turbulent Boundary Layer ◽  
Polymer Solutions

Diffusion of drag-reducing polymer solutions within a rough-walled turbulent boundary layer

2010 ◽  
Vol 22 (4) ◽  
pp. 045102 ◽  
Author(s):  
Brian R. Elbing ◽  
David R. Dowling ◽  
Marc Perlin ◽  
Steven L. Ceccio
Keyword(s):  
Boundary Layer ◽  
Turbulent Boundary Layer ◽  
Polymer Solutions ◽  
Drag Reducing Polymer

scholarly journals Specific features of coordinated variations in friction resistance and flow velocity profile in tubes at Toms effect

2021 ◽  
Vol 3 (397) ◽  
pp. 25-32
Author(s):  
V. Pavlovsky ◽  
◽  
О. Orlov ◽  
Keyword(s):  
Boundary Layer ◽  
Turbulent Boundary Layer ◽  
Velocity Profile ◽  
Flow Velocity ◽  
Polymer Solution ◽  
Polymer Solutions ◽  
Resistance Coefficient ◽  
Friction Resistance ◽  
General Law ◽  
Flow Velocity Profile

Object and purpose of research. Relationships between friction resistance coefficient and velocity distributions in the turbulent boundary layer of low-concentrated polymer solutions are investigated. These relationships are different from water because in polymer solutions the friction resistance at constant Reynolds numbers is additionally changed with solution concentrations. Materials and methods. The known experimental data on variations of the friction resistance coefficient and the velocity profiles in turbulent flows in circular tubes at changes in polymer solution concentrations. Main results. The general law of coordinated variations in friction resistance coefficient λ and flow velocity profile in the turbulent boundary layer depending on Reynolds number and polymer solution concentration. The flow models are validated, which describe the laws of velocity variations in all characteristic sections of boundary layer: laminar sublayer, buffer and logarithmic flow areas. A new non-dimensional number is introduced, which characterizes the ability of low concentrated water solutions of polymers to reduce the friction resistance. It is called the Toms effect parameter in the work. Conclusion. Results of the investigation will be useful in developing the theoretical methods for estimation of boundary layer characteristics in polymer solutions.

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