Publication Date: 05-11-2015
Abstract:
The geometry of a pump intake structure is responsible for providing an efficient water supply to a series of pumps; failure of which causes undesirable-turbulent flow patterns, flow separation; which further leads to generation of unacceptably high magnitudes of swirl, undesirable cavitation of the impeller in conjunction with excessive mechanical vibrations in the pumps.
The flow characteristics in pump intakes having multiple pump installations is involved, which consequentially demands for an empirical, as well as, a numerical methodology for the design of its intake geometry. The numerical study carried out in this paper aims at optimizing the overall fluid flow in a pump intake by the use of a commercially available CFD code. The test cases pertain to an intake with, 4 identical pumps working at duty point at the lowest water level (LWL), with a severely non-uniform and turbulent flow resulting due to the inherent constraints imposed by the intake geometry, arising due to site specific conditions. A total of three test cases are discussed, two of them have blocking arrangements aimed to optimize the fluid flow behavior. The flow is successfully optimized and a control over the flow is introduced by the unique application of the well-established fluid phenomena- “wall attachment” or the “Coanda effect” in the design of a curved surface blocking arrangement used in the ultimate case.
The geometry of a pump intake structure is responsible for providing an efficient water supply to a series of pumps; failure of which causes undesirable-turbulent flow patterns, flow separation; which further leads to generation of unacceptably high magnitudes of swirl, undesirable cavitation of the impeller in conjunction with excessive mechanical vibrations in the pumps.
The flow characteristics in pump intakes having multiple pump installations is involved, which consequentially demands for an empirical, as well as, a numerical methodology for the design of its intake geometry. The numerical study carried out in this paper aims at optimizing the overall fluid flow in a pump intake by the use of a commercially available CFD code. The test cases pertain to an intake with, 4 identical pumps working at duty point at the lowest water level (LWL), with a severely non-uniform and turbulent flow resulting due to the inherent constraints imposed by the intake geometry, arising due to site specific conditions. A total of three test cases are discussed, two of them have blocking arrangements aimed to optimize the fluid flow behavior. The flow is successfully optimized and a control over the flow is introduced by the unique application of the well-established fluid phenomena- “wall attachment” or the “Coanda effect” in the design of a curved surface blocking arrangement used in the ultimate case.
DOI: http://dx.doi.org/10.17577/IJERTV4IS110129
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