• Title/Summary/Keyword: Circulating

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Correlative Experimental Study Between The Results of Circulating Water Channel and Towing Tank Tests (회류수조와 예인수조 시험결과의 상호관계의 실험적 연구)

  • Lee, K.J.;Ra, Y.K.
    • Journal of the Society of Naval Architects of Korea
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    • v.40 no.4
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    • pp.37-45
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    • 2003
  • Model tests using 2.0m model of the series 60 form( $C_{b}$= 0.6) were carried out in the Circulating Water Channel (CWC) in the Chosun University (CU, Korea) for the purpose of a correlative study with Towing Tank (TT). Resistance, propeller open water, self propulsion and wake survey tests were carried out and the results were extrapolated to the ship scale. These results were compared with the extrapolated ship values based on the model test of 7.0m model in the TT at the Korea Research Institute of Ships and Ocean Engineering (KRISO, Korea). The CWC test results were correlated with the results of the towing tank tests.s.

Depressurized Circulating Water Channel Design Using CFD (수치 해석을 이용한 감압 회류 수조 설계)

  • 부경태;조희상;신수철
    • Journal of the Society of Naval Architects of Korea
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    • v.40 no.4
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    • pp.22-29
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    • 2003
  • New high-speed depressurized circulating water channel was designed by using the CFD code. Flow in the channel has free surface and pressure in the test section can be depressed. In this study, Flow separation and bubble occurrence were considered in designing the contraction nozzle shape for better flow uniformity Tn the test section. To supplement velocity defect due to the free surface, nozzle injection system more effective in high-speed flow was installed instead of drum system. Necessary power and injection techniques were proposed. And guide vane arrangement was analyzed to reduce the flow resistance and keep quiet free surface from ´surging´. Wave absorber was devised to reduce the wave resistance and to prevent the entrainment of air to the diffuser.

Measurement of Heat Transfer Rates and Pressure Drops in a Solid Particle Circulating Fluidized Heat Exchanger (고체입자 순환유동층 열교환기의 열전달률 및 압력강하 측정)

  • 이금배;전용두;박상일
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.9
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    • pp.817-824
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    • 2000
  • The fluidized solid particles not only increase heat transfer rates but have a cleaning function eliminating contaiminated substances caused from condensate water. An experiment was performed to measure heat transfer rates and pressure drops in a fluidized heat exchanger with circulating solid particle for constant heat transfer rate. As a results, the heat transfer rate increased by 26.9~2.6%, heat transfer coefficient by 11.9~2.7%, and pressure drop by 79.1~10.9% at the gas velocity of 6.1 ~12.1 m/s and solid particle flow rate of 100~50 kg/h with the heat exchanger of H: 50 mm, $D_p=2 in,\; and\;D_{BP}$=30 mm.

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Effects of Erythrosine on Murine Immune Functions and Methemoglobin Formation (식품 첨가물의 면역독성 및 혈액독성 - Erythrosine이 마우스의 면역기능과 Methemoglobin형성에 미치는 영향 -)

  • 황미경;윤혜정;유충규;문창규
    • Journal of Food Hygiene and Safety
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    • v.2 no.4
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    • pp.191-196
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    • 1987
  • Erythrosine used as a colouring agent in drugs, cosmetics and foods in Korea, was examined for its effects on murine immune system and methemoglobin formation. As immunotoxicologic assay parameters, we adopted circulating leukocytes and immunoorgan weights for pathotoxicology, IgM plaque forming cells and arthus reaction for humoral immunity, delayed hypersensitivity reaction of cell mediated immunity and carbon clearacnce for macrophage function. Erythrosine's effects were observed as follows; 1. Ery throsine showed no significant effects on circulating leulocyte counts and relative immunoorgan weight. 2. Erythrosine diminished IgM plaque forming cells. 3. Erythrosine decreased arthus reaction, in the dose dependent manner. 4. Erythrosine had no significant effect on delayed hypersensitivity. 5. Phagocytic and corrected phagocytic index were not affected. 6. Methemoglobin content was similar in the test and control groups.

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Correlative Experimental Study Between The Results of Circulating Water Channel and Towing Tank Tests

  • Lee, Kwi-Joo;Kim, Kyoung-Hwa;Isaacs, Karl Antony
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2003.10a
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    • pp.70-75
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    • 2003
  • Model tests using 2.0m model of the series 60 form ($C_{b}$ = 0.6) were carried out in the Circulating Water Channel(CWC) in the Chosun University(CU, Korea) for the purpose of a correlative study with Towing Tank(TT). Resistance, propeller open water, self propulsion, and wake survey tests were carried out and the results were extrapolated to the ship scale. These results were compared with the extrapolated ship values based on the model test of 7.0m model in the TT at the Korea Research Institute of Ships and Ocean Engineering (KRISO, Korea). The CWC test results were correlated with the results of the towing tank tests.

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A Study on Development of a Circulating Pump with Space Constraintst (설치공간이 제한된 순환펌프의 개발에 관한 연구)

  • Yoon, Eui-Soo;Yoo, Il-Su;Hwang, Soon-Chan;Oh, Hyoung-Woo
    • The KSFM Journal of Fluid Machinery
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    • v.14 no.1
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    • pp.24-33
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    • 2011
  • A circulating pump with installation space constraints was developed satisfying performance requirements such as flowrate, head and NPSHAv. The development procedures are composed of conceptual design, configuration design, performance analysis by CFD and performance test which were established in KIMM. The developed pump is OH4 type centrifugal pump which has a mixed-flow type impeller, a double volute and a rigid coupling. As a result of tests, the pump proved to meet all the requirements including space constraints and performance.

Numerical Analysis of Fluid and Thermal Characteristics on Live Fishing Tank of Small Fishing Boat (소형어선용 어창내의 열 유동특성 해석)

  • 한인근;문춘근;김재돌;윤정인
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.6
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    • pp.1324-1329
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    • 2001
  • The depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. This study represents the thermal characteristics of the fish hold storage during transportation. The numerical analysis in this study is the finite volume method with the SIMPLE computational algorithm to study the seawater flow behavior in the fish hold storage. The computation were carried out with the variations of the circulating flow velocity and depth of fish hold storage. As the result of the three dimensional simulations, the mean temperature doesn't almost change by the circulating flow rate. find the mean temperature is suddenly changed by the ratio of depth of fish hold storage.

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Effect of Secondary Air Injection on Emission from Sludge Incineration in a Batch-type Internally Cycloned Circulating Fluidized Bed Combustor (배치형 내부 사이클론식 순환유동층 연소로내 2차 공기 주입에 의한 슬러지 소각 유해 배가스 저감효과)

  • Jang, Seuk-Don;Shin, Dong-Hoon;Hwang, Jung-Ho
    • Journal of the Korean Society of Combustion
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    • v.7 no.3
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    • pp.16-22
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    • 2002
  • Combustion performance of an internally cycloned circulating fluidized bed for paper sludge was discussed through a series of batch type experiments. Operation parameters such as water content, feeding mass of sludge and secondary air injection rate were varied to find out the effect on the combustion performance, which was examined with carbon conversion rate and pollutant emission such as CO and NOx. A conventional solid fuel reaction was observed in the experiments of varying water content and feeding mass of the sludge, which is characterized with kinetic limited reaction zone, diffusion limited reaction zone and transition zone. Secondary air injection with swirl enhances the mixing of the gas phase as well as the solid phase, and improves combustion efficiency accompanied with higher carbon conversion rate and lower pollutant emission rate.

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Effect of Secondary Air Injection on CO and NOx Emission in an Internally Circulating Fluidized Bed Combustor (이중 순환식 유동층 연소로내에서 2차 공기 주입에 의한 CO, NOx 저감효과)

  • Jang, S.D.;Shin, D.H.;Hwang, J.H.
    • 한국연소학회:학술대회논문집
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    • 2002.06a
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    • pp.204-211
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    • 2002
  • Combustion experiments are carried out to obtain the fundamental data for application of a internally circulating fluidized bed combustor to the combustion of paper sludge wastes. Experimental parameters are identified as secondary air ratio, sludge weight and water contents. The secondary air ratio was varied from 0 to 20% and water content was 14%, 25%, 35%, 45%, 62% and sludge weight was 30g, 60g, 90g. As a result, carbon conversion ratio was higher than injection of primary air. Emission of CO and NOx reduced with an increase of secondary air injection.

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Incineration of Waste Water Sludge and Coal In a Circulating Fluidized Bed Combustor (순환유동층에서 폐수슬러지와 석탄의 혼소 특성)

  • Bae, Dal-Hee;Shun, Do-Won;Park, Jae-Hyeon;Ryu, Ho-Jung;Park, Do-Hyun
    • 한국연소학회:학술대회논문집
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    • 2004.06a
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    • pp.165-172
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    • 2004
  • Co-incineration of coal and wastewater sludge was r;erfonn:rl in a O.lMWth bench scale circulating fluidized bed combustor(CFBC) Sludge was received from a wastewater treatment plant in a dye industrial complex in Busan. Metropolis. Moisture content of received sludge was 80%. Coal and sludge mixture was prepared with weight ratio of 90/10, 85/15 and 80/20. Co-combustion characteristics of the coal and sludge mixture demonstrated stable combustion conditions. Component analysis, incineration characteristics, boiler performance was measured before and after the test and application for commercial 59MWth CFBC boiler. The release of hazardous components such as $SO_2$ and Cl was suppressed by the presence of inherent minerals of Ca, Na, K in coal and sludge mixture. Pre-drying was not essential but it was recommended for the benefits of manageability of sludge.

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