Numerical study of effects of a bellmouth on the entrance pipe flow

A numerical study was performed to investigate the effects of heating and buoyancy on the turbulent structures and transport in turbulent pipe flow. Isoflux wall boundary conditions with low and high heating were imposed. The compressible filtered Navier-Stokes equations were solved using a second order accurate finite volume method. Low Mach number preconditioning was used to enable the compressible code to work efficiently at low Mach numbers. A dynamic subgrid-scale stress model accounted for the subgrid-scale turbulence. The results showed that strong heating caused distortions of the flow structures resulting in reduction of turbulent intensities, shear stresses, and turbulent heat flux, particularly near the wall. The effect of heating was to raise the mean streamwise velocity in the central region and reduce the velocity near the wall resulting in velocity distributions that resembled laminar profiles for the high heating case.

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Numerical Study on the Migration of Two Spheres in Upward Pipe Flow

Volume 2: CFD and FSI ◽

10.1115/omae2018-77393 ◽

2018 ◽

Author(s):

Lei Liu ◽

Haining Lu ◽

Jianmin Yang ◽

Xinliang Tian ◽

Tao Peng ◽

...

Keyword(s):

Flow Velocity ◽

Poiseuille Flow ◽

Pipe Flow ◽

Deep Sea ◽

Numerical Study ◽

Critical Value ◽

Dynamic Responses ◽

Phase Flow ◽

Two Phase ◽

Offshore Engineering

Migration of particles in pipe flow is commonly seen in offshore engineering, such as vertical transport of ores in deep sea mining. As the basis of the investigation on fluid-particle two-phase flow, the interaction of two spheres in upward pipe flow is studied by direct numerical simulations in this paper. The pipe flow is set as Poiseuille flow; the Reynolds number is no more than 1250. The dynamic responses of the spheres and the flow pattern are analyzed at different flow velocity. When compared to the sedimentation of two spheres in quiescent flow, the trailing sphere in Poiseuille flow will never surpass the leading one in Poiseuille flow. As the flow velocity increases in the pipe, the spheres are easier to separate after collision. When the flow velocity exceeds a critical value, the spheres will never collide.

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311 Numerical Study of Periodical Turbulent Pipe Flow

The Proceedings of Conference of Chugoku-Shikoku Branch ◽

10.1299/jsmecs.005.2.89 ◽

2000 ◽

Vol 005.2 (0) ◽

pp. 89-90

Author(s):

Hideo UDAGAWA ◽

Tatsuo SAWADA

Keyword(s):

Pipe Flow ◽

Numerical Study ◽

Turbulent Pipe Flow

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Numerical study of pressure distribution in entrance pipe flow

Journal of Complexity ◽

10.1016/j.jco.2009.02.003 ◽

2009 ◽

Vol 25 (3) ◽

pp. 253-267 ◽

Cited By ~ 3

Author(s):

Hidesada Kanda ◽

Kenshuu Shimomukai

Keyword(s):

Pressure Distribution ◽

Pipe Flow ◽

Numerical Study

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A Numerical Study of Pulsed Turbulent Pipe Flow

Journal of Fluids Engineering ◽

10.1115/1.3242463 ◽

1985 ◽

Vol 107 (2) ◽

pp. 205-211 ◽

Cited By ~ 2

Author(s):

V. Reddy ◽

J. B. McLaughlin ◽

R. J. Nunge

Keyword(s):

Pressure Gradient ◽

Production Rate ◽

Pipe Flow ◽

Numerical Study ◽

Phase Relationship ◽

Turbulent Pipe Flow ◽

Wall Region ◽

Pulsation Frequency ◽

Axial Pressure Gradient ◽

Turbulence Production

A numerical study of fully developed turbulent pipe flow due to a sinusoidally varying (with respect to time) axial pressure gradient was carried out using a nonlinear three-dimensional model. Pseudospectral methods were used to solve the model equations. The pulsation frequency was characteristic of the wall region eddies in steady turbulent flow. Attention was focused on the viscous wall region, and it was found that the mean profiles of axial velocity, fluctuation intensities, and turbulence production rate were essentially the same as in steady flow. The fluctuation intensities and the turbulence production rate showed a definite phase relationship to the pressure gradient. The turbulence production rate was the largest at the time in the pulsation cycle at which the largest adverse pressure gradient existed.

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