Analytical Studies of Two-Dimensional Channel Turbulent Flow Subjected to Coriolis Force.

An experimental study is performed to investigate the effects of the extensional rheological properties of drag-reducing wormlike micellar solutions on the vortex deformation and turbulence statistics in two-dimensional (2-D) turbulent flow. A self-standing 2-D turbulent flow was used as the experimental set-up, and the flow was observed through interference pattern monitoring and particle image velocimetry. Vortex shedding and turbulence statistics in the flow were affected by the formation of wormlike micelles and were enhanced by increasing the molar ratio of the counter-ion supplier to the surfactant, ξ, or by applying extensional stresses to the solution. In the 2-D turbulent flow, extensional and shear rates were applied to the fluids around a comb of equally spaced cylinders. This induced the formation of a structure made of wormlike micelles just behind the cylinder. The flow-induced structure influenced the velocity fields around the comb and the turbulence statistics. A characteristic increase in turbulent energy was observed, which decreased slowly downstream. The results implied that the characteristic modification of the 2-D turbulent flow of the drag-reducing surfactant solution was affected by the formation and slow relaxation of the flow-induced structure. The relaxation process of the flow-induced structure made of wormlike micelles was very different from that of the polymers.

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Flow patterns of shallow Palic Lake induced by the dominant winds

Facta universitatis - series Architecture and Civil Engineering ◽

10.2298/fuace1201055b ◽

2012 ◽

Vol 10 (1) ◽

pp. 55-67

Author(s):

Ljubomir Budinski ◽

Djula Fabian

Keyword(s):

Numerical Model ◽

Flow Pattern ◽

Coriolis Force ◽

Wind Direction ◽

Driving Forces ◽

Open Water ◽

Flow Patterns ◽

Two Dimensional ◽

Lake Model ◽

Double Gyre

Studies of lake currents have highlighted that in case of stagnant waters winds are the dominant driving forces. This study is dealing with the influence of dominant winds on the flow pattern of Palic Lake. Action of steady winds of different directions has been tested on the lake by means of a two dimensional numerical model, while in addition to winds all other permanent factors like actual bathymetry, inflow and outflow as well the Coriolis force have been accounted for. The experiments have revealed that winds of different directions created corresponding characteristic flow patterns (in base plot), which were similar in cases of winds having opposite directions. However, in such cases the direction of flow was opposite. Moreover, the Palic Lake model produced the well known double-gyre flow pattern: in the coastal strip the direction of the current corresponded to the wind direction, while it was opposite in the domain of open water.

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Solutions of Navier-Stokes Equation with Coriolis Force

Advances in Mathematical Physics ◽

10.1155/2017/7042686 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Sunggeun Lee ◽

Shin-Kun Ryi ◽

Hankwon Lim

Keyword(s):

Diffusion Equation ◽

Stokes Equation ◽

Coriolis Force ◽

Potential Flow ◽

Convective Diffusion ◽

Navier Stokes ◽

Coriolis Effect ◽

Two Dimensional ◽

Navier Stokes Equation ◽

Convective Diffusion Equation

We investigate the Navier-Stokes equation in the presence of Coriolis force in this article. First, the vortex equation with the Coriolis effect is discussed. It turns out that the vorticity can be generated due to a rotation coming from the Coriolis effect, Ω. In both steady state and two-dimensional flow, the vorticity vector ω gets shifted by the amount of -2Ω. Second, we consider the specific expression of the velocity vector of the Navier-Stokes equation in two dimensions. For the two-dimensional potential flow v→=∇→ϕ, the equation satisfied by ϕ is independent of Ω. The remaining Navier-Stokes equation reduces to the nonlinear partial differential equations with respect to the velocity and the corresponding exact solution is obtained. Finally, the steady convective diffusion equation is considered for the concentration c and can be solved with the help of Navier-Stokes equation for two-dimensional potential flow. The convective diffusion equation can be solved in three dimensions with a simple choice of c.

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Computational Fluid Dynamics Techniques for Flows in Lapple Cyclone Separator

Materials Science Forum ◽

10.4028/www.scientific.net/msf.498-499.179 ◽

2005 ◽

Vol 498-499 ◽

pp. 179-185

Author(s):

A.F. Lacerda ◽

Luiz Gustavo Martins Vieira ◽

A.M. Nascimento ◽

S.D. Nascimento ◽

João Jorge Ribeiro Damasceno ◽

...

Keyword(s):

Fluid Dynamics ◽

Experimental Data ◽

Computational Fluid Dynamics ◽

Turbulent Flow ◽

Reynolds Stress ◽

Cyclone Separator ◽

Two Dimensional ◽

Stress Components ◽

Computational Fluid Dynamics Cfd

A two-dimensional fluidynamics model for turbulent flow of gas in cyclones is used to evaluate the importance of the anisotropic of the Reynolds stress components. This study presents consisted in to simulate through computational fluid dynamics (CFD) package the operation of the Lapple cyclone. Yields of velocity obtained starting from a model anisotropic of the Reynolds stress are compared with experimental data of the literature, as form of validating the results obtained through the use of the Computational fluid dynamics (Fluent). The experimental data of the axial and swirl velocities validate numeric results obtained by the model.

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The Lift on a Wing in a Turbulent Flow

Aeronautical Quarterly ◽

10.1017/s0001925900006569 ◽

1973 ◽

Vol 24 (3) ◽

pp. 155-166 ◽

Cited By ~ 26

Author(s):

R Jackson ◽

J M R Graham ◽

D J Maull

Keyword(s):

Aspect Ratio ◽

Turbulent Flow ◽

Grid Turbulence ◽

Two Dimensional ◽

Rectangular Element

SummaryExperiments are described in which the lift on a rectangular element of a two-dimensional wing and on a finite aspect ratio wing has been measured in grid turbulence. By measuring the spectrum of the lift and the spectrum of the turbulence upwash component, an experimental value for the turbulent admittance may be found. This is compared with a calculated value based upon linearised theory.

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