• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.89-94
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• 2002

n general, the function of intake structure, whether it be a open channel, a fully wetted tunnel, a sump or a tank, is to supply an evenly distributed flow to a pump station. An even distribution of flow, characterized by strong local flow, can result in formation of surface or submerged vortices, and with certain low values of submergence, may introduce air into pump, causing a reduction of capacity and efficiency, an increase in vibration and additional noise. Uneven flow distribution can also increase or decrease the power consumption with a change in total developed head. To avoid these sump problems pump station designers are considered intake structure dimensions, such as approaching upstream, baffle size, sump width, width of pump cell and so on. From this background, flow characteristics of intake within sump are investigated numerically to obtain the optimal sump design data. The sump model is designed in accordance with HI code.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.597-600
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• 2002

In general, the function of intake structure, whether it be a open channel, a fully wetted tunnel, a sump or a tank, is to supply an evenly distributed flow to a pump station. An even distribution of flow, characterized by strong local flow, can result in formation of surface or submerged vortices, and with certain low values of submergence, may introduce air into pump, causing a reduction of capacity and efficiency, an increase in vibration and additional noise. Uneven flow distribution can also increase or decrease the power consumption with a change in total developed head. To avoid these sump problems pump station designers are considered intake structure dimensions, such as approaching upstream, baffle size, sump width, width of pump cell and so on. From this background, flow characteristics of intake within sump are Investigated numerically to obtain the optimal sump design data. The sump model is designed in accordance with HI code.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.593-597
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• 2005

In order to study the characteristics of the subsurface vortex the flow fields of the three pump sump models were analysed by the numerical simulation. The calculation results show that there are circulation flows in the pump sump model and maximum vorticity strength which make iso-surface from the wall to the pump inlet could be used for predicting the subsurface vortex generation. Also, the flow field for the sump model with anti-vortex devices simulated and the results shows that there is no vorticity value which make iso-surface from the sump wall to the pump inlet.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.8
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• pp.849-855
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• 2015

A better flow condition for the intake of pump is provided by the sump pump that connects the forebay to the intake of the pump station. If the suction sump is improperly shaped or sized, air-entraining vortices or submerged vortices may develop. These phenomena may greatly affect pump operation if vortices become sufficiently large. Moreover, any remaining vortices in the pump flow passage may result in an increase in the noise and vibration of the pump. Therefore, the vortices in the pump flow passage must be reduced to achieve good pump sump station performance. In this study, the effect of suction pipe leaning angle on the pump sump's internal flow is investigated. Additionally, a pipe type with an elbow shape is investigated. The results show that the air entraining vortices occur under the condition of a water level ratio H/D = 1.31 for each suction pipe type.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.589-592
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• 2005

In general, the function of intake structure, whether it be a open channel, a fully wetted tunnel, a sump or a tank, is to supply an evenly distributed flow to a pump station. An even distribution of flow, characterized by strong local flow, can result in formation of surface or submerged vortices, and with certain low values of submergence, may introduce air into pump, causing a reduction of capacity and efficiency, an increase in vibration and additional noise. Unfortunately in order to design the sump station, the reasonable code or the standards weren't presented yet in Korea. Thus, some researchers had often referred the HI code, JSME code or CEN code to design the sump station. This study aims to prescribe the standard of sump design which were matched well the Korean pump station. Thus, the HI code and TSJ code would be interpreted fully to Korean language, the part of interpreted clauses of the western codes would be selected to compose the standard.

• The KSFM Journal of Fluid Machinery
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• v.20 no.1
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• pp.74-80
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• 2017

Pump sump system or pumping stations are built to draw water from a source such as river and used for irrigation, thermal power plants etc. If pump sump is improperly shaped or sized, air entraining vortices or submerged vortices may develop. This may greatly affect pump operation if vortices grow to an appreciable extent. Moreover, the noise and vibration of the pump can be increased by the remaining of vortices in the pump flow passage. Therefore, the vortices in the pump flow passage have to be reduced for a good performance of pump sump station. In this study, the effect of pump intake leaning angle and flow rate on the pump sump internal flow has been investigated. There are three cases with different leaning angle. Moreover, a pipe type with elbow also has been studied. The flow rate with three classes of air entraining vortices has been examined and investigated by decreasing the water level. The result shows that the air entraining vortices easily occurs at the pump intake with large leaning angle. Moreover, the elbow type of the pump intake easily occurs air entraining vortices at the high flow rate (or velocity) in comparison to other pump intake type.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.673-680
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• 2017

sump pump is a system that draws in water that is stored in a dam or reservoir. They are used to pump large amounts of water for cooling systems in large power plants, such as thermal and nuclear plants. However, if the flow and sump pump ratio are small, the flow rate increases around the inlet port. This causes a turbulent vortex or swirl flows. The turbulent flow reduces the performance and can cause failure. Various methods have been devised to solve the problem, but a correct solution has not been found for low water level. The most efficient solution is to install an anti-vortex device (AVD) or increase the length of the sump inlet, which makes the flow uniform. This paper presents a computational fluid dynamics (CFD) analysis of the flow characteristics in a sump pump for different sump inlet lengths and AVD types. Modeling was performed in three stages based on the pump intake, sump, and pump. For accurate analysis, the grid was made denser in the intake part, and the grid for the sump pump and AVD were also dense. 1.2-1.5 million grid elements were generated using ANSYS ICEM-CFD 14.5 with a mixture of tetra and prism elements. The analysis was done using the SST turbulence model of ANSYS CFX14.5, a commercial CFD program. The conditions were as follows: H.W.L 6.0 m, L.W.L 3.5, Qmax 4.000 kg/s, Qavg 3.500 kg/s Qmin 2.500 kg/s. The results of analysis by the vertex angle and velocity distribution are as follows. A sump pump with an Ext E-type AVD was accepted at a high water level. However, further studies are needed for a low water level using the Ext E-type AVD as a base.

• The KSFM Journal of Fluid Machinery
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• v.12 no.4
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• pp.14-22
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• 2009

The head-capacity curves for pumps developed by the pump manufacturer are based on tests of a single pump operating in a semi-infinite basin with no close walls or floors and with no stray currents. Therefore, flow into the pump intake is with no vortices or swirling. However, pump station designers relying on these curves to define the operating conditions for the pump selected sometimes meet the reductions of capacity and efficiency, as well as the increase of vibration and additional noise, which were caused by air-entered flow in the pump station. From this background, the authors are carrying out a systematic study on the flow characteristics of intakes within a sump of pump station model. Multi-intake sump model with anti-submerged vortex device basin is designed and the characteristics of submerged vortex is investigated in the flow field by numerical simulation. In this study, a commercial CFD code is used to predict the vortex generation in the pump station accurately. The analysed results by CFD show that the vortex structure and effect of anti-submerged vortex device are different at each pump intake channel.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.95-101
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• 2002

The head-capacity curves for pumps developed by the pump manufacturer are based on tests of a sin91e pump operating in a semi-infinite pool with no nearby walls or floors and no stray currents. Hence, flow into the pump suction is symmetrical with no vortices or swirling. Pump station designers rely on these curves to define the operating conditions for the pump selected. But various constraints such as size, cost, and limitations on storage time require walls, floors, and pump intakes to be close proximity to each other. From this background, the authors are carrying out a systematic study on the flow characteristics of intakes within a sump found within a sump of pump stations. Model pump intake basin is designed and PIV is adopted as a measuring tool to capture the instantaneous flow patterns. Special attention is paid to investigate the flow patterns near the free surface due to different clearances from back-wall to vertical intake pipe with bell mouse and without. Moreover, the locations and vorticities of the various types of vortices that were found in the examinations are discussed.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.592-595
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• 2011

A numerical investigation on a suction vortices, free vortices and subsurface vortices behavior in the model sump system with multi-intakes is performed A test model sump and piping system were designed based on Froude similitude for the prototype of the recommended structure layout by HI-9.B Standard for Pump Intake Design of the Hydraulic Institute. A numerical analysis of three dimensional multiphase flows through the model sump is performed by using the finite volume method of the CFX code with multi-block structured grid systems. A ${\kappa}-{\omega]$ ShearStressTransportturbulencemodelandthe Rayleigh-Plesset cavitation model are used for solving turbulence cavitating flow. From the numerical analysis, several types of vortices are reproduced and their formation, growing shedding and detailed vortex structures are investigated. To reduce abnormal vortices, an anti-vortex device is considered and its effect is investigated and discussed.