• 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.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.170.2-170.2
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• 2010

The amount of the heating and cooling energy of water source heat pump using the raw water from the Paldang water intake station is investigated in the study. The Han river water is conveyed in the large-size shallowly buried pipe. Averaged water temperature at the position, 27 km from the Paldang water intake station, is increased by $1.11^{\circ}C$ due to the geothermal energy transfer under the ground, therefore the raw water has more thermal energy than the river water. To estimate of the thermal energy for the raw water, it is assumed that the water source heat pump is used for the heating and cooling ventilation. When $5.0^{\circ}C$ temperature difference energy of the raw water is used in the heat pump system all the year except for the January and February in which $3.0^{\circ}C$ temperature difference energy is used. It is predicted that total 5,766.3 Tcal could be used in the metropolitan area a year, which is about 3.0% of the river water unutilized energy resources.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.211-216
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• 2006

This study was carried out to investigate the effect of greenhouse cooling by a geothermal heat pump system on greenhouse temperature and growth of vegetable transplants in summer season. Greenhouse air temperature in day time was $3-4^{\circ}C$ lower in fog plus shading system than in shading, while in night time that was $5-7^{\circ}C$ lower in geothermal heat pump (GHP) plus shading system compared to shading or fogplus shading. system. Plant height of cucumber, tomato and hot pepper transplants was shortened in GHP plus shading compared to shading or fog plus shading system. And Leaf area and dry weight were slightly decreased in GHP plus shading compared to the other systems. Therefore, healthy transplant index on cucumber, tomato and hot pepper was higher in GHP plusshading than in shading or fogplusshading system.

• Progress in Medical Physics
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• v.14 no.1
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• pp.51-53
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• 2003

The results of the measured specific activities of Rn-222 in water for public water supply pump houses (wells) of Ulaanbaatar City, Mongolia using the HP-Ge gamma-spectrometer, are described. The average of the specific radioactivies for the Rn-222 were for the station “Centre” 82.59 Bq/l, station “Combinat” 91.35 Bq/l and station “Makh” 158.25 Bq/l, respectively.

• 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.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.209-215
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• 2001

The head-capacity curves for pumps developed by the pump manufacturer are based on tests of a single 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 in 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, side-wall and back-wall due to different clearances from back-wall to vertical in take pipe. Moreover, the locations and vorticities of the various types of vortices that were found in the examinations are discussed.

• The KSFM Journal of Fluid Machinery
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• v.7 no.1 s.22
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• pp.51-57
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• 2004

The waterhammer has recently become more important because the pumping stations were big and the systems conveying the fluid through the large and long transmission pipelines were complex. When the pumps are started or stopped for the operation or tripped due to the power failure, the hydraulic transients occur as a result of the sudden change in velocity As the pressure waves are propagating between the pumping station and the distributing reservoir, the pressure inside the pipe drops to the liquid vapor pressure with the pipeline profile, at which time a vapor cavity forms, and finally the column separation occurs. If the pressure in the pipe is less than the atmospheric pressure, the pipe can be collapsed and destroyed after the water columns separated by the vapor cavity rejoin. During the reverse flow, the pressure is so abnormally increased at the pumping station that the accident of flooding may happen due to the failure of system. In this paper, the field tests on the waterhammer by the startup, stoppage, and power failure of a centrifugal pump were carried out for Yongma transmission pumping station in Seoul. The experimental results were compared with that of the numerical calculations, in which results the procedure of controlled pump normal shut-down and the two-step closing mode of controlling the ball valve for pump emergency stop are proposed to reduce the pressure surge.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.199-207
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• 2004

Water supply facilities are recently getting larger according as domestic waterworks become multi regional water supply system. Large water supply facilities generally consist of the intake pumping station, water treatment station and water supply & distribution facilities. Although pumping stations and pipeline systems are used to pump up water, it often happens pipeline damage and flooding accident by the water hammer. As a result of this study, a pumping station is guaranteed by the computer simulation and field test analysis. Therefore these are contributed safety operation in pumping station through adjustment of the pumping station safety plan, air valve and valve closing time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.5
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• pp.1192-1200
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• 2007

A general rainfall outflow in urban drainage has early time of concentration because urban drainage areas are most paved area. In general, rainfall outflow is flowed in drainage pump station and is discharged to rivers in urban areas. However it is excluded through drainage pumps about a heavy rainfall which exceed the design rainfall and the rainfall outflows increase the urban inundation risk. A current pump operation is control according to water level of collecting well or reservoir in drain pump station. But recently, the localized downpours are happened frequently in urban drainage and the current pump stations are frequently incapable of the heavy rainfall outflows. In this study, a real urban inundation was simulated and the drain capacity of drain pump station was evaluated by analysis about flood-factor in urban underground passage. Then the analysis about the inundation was done by the simulation about the real rainfall which cause the inundation. Also, in the simulation the inundation risk and the evaluation of flood-factor were analyzed according to change of the pump operation rule.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.6
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• pp.793-802
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• 2022

Non-structural improvements to urban drainage systems are necessary to overcome the elevated levels of urban flood damage. This study proposed a type of automatic pump/gate operation technology for urban pump stations that takes reservoir inflows and river water levels into account and its performance is compared with the current operation using the concept of residual flow-based resilience. The proposed automatic operation relies on three pump operations and two gate operations. The water depth at the monitoring node was used for the pump operation, and the monitoring node was selected in consideration of the first overflow node and the maximum overflow node. The target area is the Daegu Bisan urban pump station, and the rainfall data consisted of probability rainfall sets with durations of 30 minutes, 60 minutes, 90 minutes and 120 minutes, and frequencies of 30, 50, and 70 years. As a result of the application of the proposed operation, differences in the resilience between the automatic operation and the current operation were at least 5.20E-05 with a maximum of 8.07E-04. The longer the duration is, the greater the difference in the resilience.