Analysis of drag reduction by polymers in a turbulent channel flow
نویسندگان
چکیده
We develop a model-based approach for studying the influence of polymers on drag reduction in a turbulent channel flow. Our simulation-free method utilizes turbulence modeling in conjunction with the analysis of stochastically forced linearized equations to capture the effect of velocity and polymer stress fluctuations on the turbulent viscosity and drag. We demonstrate that the essential drag-reducing trends observed in direct numerical simulations are captured by our approach.
منابع مشابه
Turbulent Drag Reduction by Spanwise Wall Oscillations
The objective of this paper is to examine the effectiveness of wall oscillation as a control scheme of drag reduction. Two flow configurations are considered: constant flow rate and constant mean pressure gradient. The Navier-Stokes equations are solved using Fourier-Chebyshev spectral methods and the oscillation in sinusoidal form is enforced on the walls through boundary conditions for the sp...
متن کاملPolymer flexibility and turbulent drag reduction.
Polymer-induced drag reduction is the phenomenon by which the friction factor of a turbulent flow is reduced by the addition of small amounts of high-molecular-weight linear polymers, which conformation in solution at rest can vary between randomly coiled and rodlike. It is well known that drag reduction is positively correlated to viscous stresses, which are generated by extended polymers. Rod...
متن کاملParametric study of a viscoelastic RANS turbulence model in the fully developed channel flow
One of the newest of viscoelastic RANS turbulence models for drag reducing channel flow with polymer additives is studied in different flow and rheological properties. In this model, finitely extensible nonlinear elastic-Peterlin (FENE-P) constitutive model is used to describe the viscoelastic effect of polymer solution and turbulence model is developed in the k-ϵ-(ν^2 ) ̅-f framework. The geome...
متن کاملشبیهسازی عددی جریان آشفته کانال نیمموج با سطوح آبدوست و آبگریز
In the first part of the present study, a two dimensional half-corrugated channel flow is simulated at Reynolds number of 104, in no-slip condition (hydrophilic surfaces( using various low Reynolds turbulence models as well as standard k-ε model; and an appropriate turbulence model (k-ω 1998 model( is proposed. Then, in order to evaluate the proposed solution method...
متن کاملAnalysis of air injection system for drag reduction in high speed vessels using numerical simulation software ANSYS-Fluid Flow
Many existing phenomena in nature are considered new design ideas in various fields of industry. Bionics is the application of biological methods and systems found in nature to the study and design of engineering systems and modern technology. By performing bionic review, the researchers found the penguins by delivering air locked under their wings and creating air bubbles, the drag significant...
متن کامل