Velocity Distribution of Extensional Flow Fields in an Eccentric Cylinder of an Extensional Extruder

A special vertical pumping system was designed for cooling system of a power plant. In order to study flow pattern and hydraulic performances of vertical pumping system with bell inlet and symmetric volute outlet, especially the flow fields in the suction passage of pumping system, the incompressible N-S equations are solved by the finite volume method. Base on the k-ε model with Wall-Function Law, the SIMPLEC algorithm is applied for the solution of the discretization governing equation. Using multiple reference frames, solutions of the flow fields of whole vertical pumping system at a Reynolds number of more than 113,000 for flow in the pumping system are presented. The normal height of pumping system is put forward. The hydraulic performances of pumping system at the different operating points near to the Best Efficiency Point (BEP) were predicted. A model pumping system was designed to test the performances of the system and the measurements of velocity distribution in outlet section of the suction passage were taken. The velocity distribution of measurements and the velocity distribution of computation in outlet section of suction passage show an asymmetrical flow field even under the operation at BEP. In general the hydraulic condition of suction passage can meet the requirements of pump operation. The differences between the computational results and the measurements results are discussed.

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An Application of 3D-PIV to the Flow Measurements in Pump Sump

Volume 2: Fora, Parts A and B ◽

10.1115/fedsm2007-37475 ◽

2007 ◽

Author(s):

Chao Liu ◽

Daliang Li ◽

Jiren Zhou ◽

Fangping Tang

Keyword(s):

Velocity Distribution ◽

Flow Condition ◽

Flow Fields ◽

Numerical Calculations ◽

Test Rig ◽

Flow Measurements ◽

Pump Performance ◽

Bell Mouth ◽

Measurement Results ◽

Pump Sump

Flow condition in the pump sump is of most importance to the pump performance. A test rig was designed for the measurements of velocity distribution. The 3D-PIV was applied to the measurements of the flow fields under the bell mouth of the pump in the opening sump. The calibrations for 3D-measurements at different sections in the pump sump were made before the test. The flow fields under the bell mouth of test pump were obtained and a 3D view of velocity vectors map was given. The measurement results of the flow fields are compared with the existing results from the experiments and numerical calculations. Analysis of flow condition in the pump sump is conducted.

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Upper Bounds and Saint-Venant’s Principle for Incompressible Potential-Flow Fields

Journal of Applied Mechanics ◽

10.1115/1.3627275 ◽

1965 ◽

Vol 32 (3) ◽

pp. 661-664 ◽

Cited By ~ 3

Author(s):

R. L. Drake ◽

P. C. Chou

Keyword(s):

Velocity Distribution ◽

Upper Bound ◽

Potential Flow ◽

Cylindrical Channel ◽

Rectangular Channel ◽

Flow Fields ◽

Upper Bounds ◽

Axially Symmetric

An upper-bound approach to Saint-Venant’s principle is presented for incompressible potential-flow fields. Upper bounds for the velocity and its potential are found for the flow in a rectangular channel and in an axially symmetric cylindrical channel. It is found that any deviation in velocity distribution at the entrance of the channel which does not change the net flow attenuates to a negligible quantity beyond a section which is at a distance of two channel widths from the entrance.

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Photon-correlation velocimetry of polystyrene solutions in extensional flow fields

Polymer ◽

10.1016/0032-3861(82)90240-3 ◽

1982 ◽

Vol 23 (10) ◽

pp. 1435-1442 ◽

Cited By ~ 49

Author(s):

K. Gardner ◽

E.R. Pike ◽

M.J. Miles ◽

A. Keller ◽

K. Tanaka

Keyword(s):

Extensional Flow ◽

Flow Fields ◽

Photon Correlation

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Accuracy Investigation of Active Flow Control Using Synthetic Jets

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.741.475 ◽

2015 ◽

Vol 741 ◽

pp. 475-480

Author(s):

Na Gao ◽

Chen Pu ◽

Bao Chen

Keyword(s):

Flow Control ◽

Velocity Distribution ◽

Active Flow Control ◽

Flow Fields ◽

Synthetic Jet ◽

Synthetic Jets ◽

Experimental Results ◽

Center Line ◽

Mean Velocity ◽

The Mean

2nd order implicit format is implemented in the Navier-Stokes code to deal with instantaneous item unsteady flows. Three simulations are made to testify the method on flow control. First, the external flow fields of synthetic jets are simulated, the mean velocity on the center line, the jet width and velocity distribution are compared well with experimental results. Secondly, the flow fields of synthetic jet in a crossflow are simulated, orifice slot, the mean velocity on the center line and velocity distribution are compared well with experimental results. Finally, the flow control experiments on separation of airfoil are simulated, control methods include steady suction and synthetic jets. Both methods show their ability to favorably effect the flow separation, shortening the length of separation bubble and improving the pressure levels in separation areas in different degrees.

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