• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.43-47
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• 2019

In this study, capability of an air slot in a siphon spillway for controlling outflow discharge is investigated through hydraulic experiments. Arc and rectangular shapes of air slot are considered and the open area of air slot can be varied. Complex air-regulated flow occurs inside the the siphon spillway when the air slot is installed on it. The same discharge is measured at the same water level inside the reservoir when the water level rises or falls. Nondimensional discharge through the siphon spillway increases slowly as nondimensional open area of the air slot increases. The hydraulic experiments show that the control of outflow discharge of siphon spillway is possible by controlling the open area of the air slot.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.671-674
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• 2011

An experimental test facility for the complete characteristics of pumps is constructed at KIMM(Korea Institute of Machinery and Materials). This paper describes the test facility and test technique of the complete characteristics of pumps, together with a experimental test result for a reactor coolant pump.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.2
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• pp.24-30
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• 2005

This research presents a modeling and a manufacturing method of screw flow meter. This paper introduces the efficient design and manufacturing method of screw type flow meter using reverse engineering and test technology. The methods introduced this paper utilize the reverse engineering that is increasing accuracy of modeling and manufacturing of reverse model. And then it can be used in performance test with hydraulic test equipment. Hence this can be used in the basic document for development of the quite accurate flowmeter.

• Proceedings of the Korean Reliability Society Conference
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• 2011.06a
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• pp.281-288
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• 2011

Hydraulic hose assemblies deliver a fluid power in various oil pressure equipments such as construction machinery, automobile, aircraft, industrial machinery, machine tools, and machinery for ships, or they are used as pipes in oil pressure circuit. However, as the traditional measure for estimating life under the influence of various external factors incurs hardship in terms of time and expenses, it is essential to take accelerated life test by choosing the factor that suits the usage condition of the test object. The objective of the this study is to propose a acceleration model that takes both temperature and pressure without flexing condition into consideration. The life that is calculated by the equation for evaluating life and the test data show similar slopes as a result of comparing and analyzing the equation for evaluating life that is obtained in this research and the test data, which illustrates that they estimate life similarly, and the proposed equation is proved to be an accelerated life equation that presents the test results.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.601-606
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• 2005

This research presents a modeling and a manufacturing method of screw flow meter. This paper introduces the efficient design and manufacturing method of screw type flow meter using reverse engineering and test technology. The methods introduced this paper utilize the reverse engineering that is increasing accuracy of modeling and manufacturing of reverse model. And then it can be used in performance test with hydraulic test equipment. Hence this can be used in the basic document for development of the quite accurate flowmeter.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.132-137
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• 2005

This research presents a modeling and a manufacturing method of screw type flow meter. This paper introduces the efficient design and manufacturing method of screw type flow meter using reverse engineering and test technology. The methods introduced this paper utilize the reverse engineering that is increasing accuracy of modeling and manufacturing of reverse model. And then it can be used in performance test with hydraulic test equipment. Hence this can be used in the basic document for development of the quite accurate flow meter.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.159.2-159.2
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• 2011

Hyundai Heavy Industries has developed a tidal current energy converter utilizing the accumulated technology as the world largest constructor for ship and offshore structures. The model has two sets of turbines in both ends in order to utilize the bi-directional current flows in flood and ebb tide. The torque produced by turbine in tidal current is directly delivered to generator along the horizontal axis, in which the turbine, gear, generator, gear and turbine are connected successively. The manufactured model for field test has the turbine diameter of 5 meters to produce the maximum power of 500kW at maximum current speed of 5m/s. The technical verification of tidal power converter was performed by means of small scale model test in towing tank as well as field test at the Strait of Uldolmok located in Jindo of Jeollanamdo province. Field test was performed by mounting the tidal current converter on the SEP(Self Elevating Platform) which could lower the 4 vertical legs on the seabed and could elevate platform over the water surface using the hydraulic power for itself. The field test performed for a month shows that power output is similar or larger compared with the expected one in design stage. This paper presents the development of tidal current energy converter and real sea field test by Hyundai Heavy Industries. This project has finished successfully and provided the technical advance toward commercial services for tidal current power generation in the south-west region in Korea.

• Journal of Hydrogen and New Energy
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• v.31 no.4
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• pp.387-394
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• 2020

A parametric study of a 2.5 kW class propeller type micro hydraulic turbine was performed. In order to analyze the internal flow characteristics in the hydraulic turbine, three dimensional Reynolds-averaged Navier-Stokes equations with shear stress transport turbulence model were used and the hexahedral grid system was used to construct computational domain. To secure the reliability of the numerical analysis, the grid dependency test was performed using the grid convergence index method based on the Richardson extrapolation, and the grid dependency was removed when about 1.7 million nodes were used. For the parametric study, the axial distance at shroud span (L) between the inlet guide vane and the runner, and the inlet and outlet blade angles (β₁, β₂) of the runner were selected as the geometric parameters. The inlet and outlet angles of the runner were defined in the 3 spans from the hub to tip, and a total of 7 geometric parameters were investigated. It was confirmed that the outlet angles of the runner had the most sensitive effect on the power and efficiency of the micro hydraulic turbine.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.516-523
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• 2020

Since the aging of coastal structures have been increased, the researches about the reinforcements of the existing aged structures are needed. Especially, the existing armor units placed on rubble mound structures should satisfy the stability against the increased design wave conditions. However the researches about these design problems have not been performed. In this study, the hydraulic model tests to investigate the stability number about the additionally placed armor unit were conducted. The main armor unit is a Tetrapod. The test results showed that the stability number (Kd) for additionally placed armor units(Tetrapod) increased up to maximum 10% comparing with that for 2 layers tetrapod (Kd = 8) within these test conditions with the pattern placing for existing armor layers and the stable armor layer slope for the non overtopping condition.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.201-204
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• 2008

Vortex and swirl occurring in a pump suction intake sump normally reduce the performance and disturb the safe operation of the circulation water pump in thermal power plants. This paper presents a case study of one particular intake sump design via a CFD analysis and a hydraulic model testing. The physical experiments and numerical analysis were performed under two flow and three level variation conditions. The vortex patterns around the pump suction pipe have been predicted by a commercial CFD code with the k-${\varepsilon}$ model. The model tests were conducted on a 1/10 model for a practical intake sump. The location, number and general pattern of the free surface vortex and submerged vortex predicted by CFD simulation were found to be a good agreement with those observed in the model testing.