• Title/Summary/Keyword: Material circulation

Search Result 289, Processing Time 0.028 seconds

Numerical Evaluation of the Cooling Performance of a Core Catcher Test Facility

  • Lee, Dong Hun;Park, Ik Kyu;Yoon, Han Young;Ha, Kwang Soon;Jeong, Jae Jun
    • Journal of Energy Engineering
    • /
    • v.22 no.1
    • /
    • pp.8-16
    • /
    • 2013
  • A core catcher is considered as a promising engineered system to stabilize the molten corium in the containment during a postulated severe accident in a nuclear power plant. Conceptually, the core catcher consists of a carbon steel body, sacrificial material, protection material, and engineered cooling channel. The cooling capacity of the engineered cooling channel should be guaranteed to remove the decay heat of the molten corium. The flow in ex-vessel core catcher is a combined problem of a two-phase flow in the engineered cooling channel and a single-phase natural circulation in the whole core catcher system. In this study, the analysis of the test facility for the core catcher using the CUPID code, which is a three-dimensional thermal-hydraulic code for the simulation of two-phase flows, was carried out to evaluate its cooling capacity.

A Study on Frank Gehry's Architectural Changes After the Art Gallery of Ontario (온타리오 미술관 이후 프랭크 게리의 건축적 변화 연구)

  • Lee, Jae-In
    • Journal of the Architectural Institute of Korea Planning & Design
    • /
    • v.34 no.2
    • /
    • pp.95-106
    • /
    • 2018
  • This study aimed at revaluating Frank Gehry's freeform constructions. To this end, the study analyzed the way the space composition and circulation system of general constructions are connected with newly extended parts in the Art Gallery of Ontario and, based on this, comparatively analyzed freeform constructions before and after the art gallery, finding out what changes were made in the exterior and interior spaces of freeform constructions built after the art gallery. The results of the study are as follows. First, starting from extending the Art Gallery of Ontario, Gehry came to use glass instead of metal as main material of freeform constructions. In order to create the circulation connecting the existing building and the extended mass, Gehry applied continuing circulation for the first time to the gallery. Third, in addition to design motives, such as the woodblock print depicting a carp by Hiroshige, still life depicting a glass bottle by Morandi and the crease of the shawl in Vermeer's paintings, which Gehry applied to freeform constructions, the design motif which was recently acquired from Pyrenees rock was added. Fourth, the trend of mall construction appeared before and after the Art Gallery of Ontario. Finally, Gary used the shape of fish as a design motif for his work at an important turning point in his Freeform Architecture.

Investigation of condensation with non-condensable gas in natural circulation loop for passive safety system

  • Jin-Hwa Yang;Tae-Hwan Ahn;Hwang Bae;Hyun-Sik Park
    • Nuclear Engineering and Technology
    • /
    • v.55 no.3
    • /
    • pp.1125-1139
    • /
    • 2023
  • The system-integrated modular advanced reactor 100 (SMART100), an integral-type pressurized water small modular reactor, is based on a novel design concept for containment cooling and radioactive material reduction; it is known as the containment pressure and radioactivity suppression system (CPRSS). There is a passive cooling system using a condensation with non-condensable gas in the SMART CPRSS. When a design basis accident such as a small break loss of coolant accident (SBLOCA) occurs, the pressurized low containment area (LCA) of the SMART CPRSS leads to steam condensation in an incontainment refuelling water storage tank (IRWST). Additionally, the steam and non-condensable gas mixture passes through the CPRSS heat exchanger (CHX) submerged in the emergency cooldown tank (ECT) that can partially remove the residual heat. When the steam and non-condensable gas mixture passes through the CHX, the non-condensable gas can interrupt the condensation heat transfer in the CHX and it degrades CHX performance. In this study, condensation heat transfer experiments of steam and non-condensable gas mixture in the natural circulation loop were conducted. The pressure, temperature, and effects of the non-condensable gas were investigated according to the constant inlet steam flow rate with non-condensable gas injections in the loop.

Material Transfer Agreement for Human Material (인체 유래 물질과 관련된 계약)

  • Kim, Jang-Han
    • The Korean Society of Law and Medicine
    • /
    • v.8 no.1
    • /
    • pp.9-34
    • /
    • 2007
  • Human material is considered as an independent object after departing from human body. But unlike other materials, that is not allowed for the trading because of the nature of personality. According to the present legal system, the human material is only permitted to donate to the researcher or biobank for scientific study. Bur after the collection, the human materials are regarded as a valuable assets and the collectors want to get more economic gains. If the neutral modulators serve for the justifiable circulation. The economic motivations could be prevented within material transfer processes. In real life, the neutral modulator is hard to find and most of partipants are involved in the economic interests. In this situation, it may be justifiable to permit the person who donate his body material to pursue reach through right on his material. The problem is how to measure the value of human material and how to treat the informed consent. If the essential portion of human personality is contributed to the value of human material and if only his material can be served for the invention, the tissue donator can get economic interests on his body material as his property. That is based on the rule of processing of human efforts on civil law.

  • PDF

Comparison of Solid Circulation Characteristics with Change of Lower Loop Seal Geometry in a Circulating Fluidized Bed (순환유동층에서 하부 루프실 형태 변화에 따른 고체순환 특성 비교)

  • Lee, Dong-Ho;Jo, Sung-Ho;Jin, Gyoung-Tae;Yi, Chang-Keun;Ryu, Ho-Jung;Park, Seung Bin
    • Korean Chemical Engineering Research
    • /
    • v.52 no.4
    • /
    • pp.522-529
    • /
    • 2014
  • Circulating fluidized bed system consists of SEWGS reactor - lower loop seal - regeneration reactor - riser - cyclone - upper loop seal has been used for solid circulation between the SEWGS reactor and the regeneration reactor in a SEWGS system for pre-combustion $CO_2$ capture. A vertical type lower loop seal has been used in current system but this lower loop seal requires high gas flow rate through the lower loop seal for fluidization and smooth solid circulation, and consequently, causes slugging behavior sometimes. To overcome these disadvantages, inclined type lower loop seal was proposed by this study. Solid circulation characteristics with change of lower loop seal geometry were measured and compared in a bubbling - bubbling - riser type circulating fluidized bed using $CO_2$ absorbent (P-78) as bed material at ambient temperature and pressure. We could conclude that the inclined lower loop seal is better than the vertical type lower loop seal from the viewpoints of minimum flow rate requirement for stable solid circulation and solid height change during solid circulation.

Analyzing the Effect of Food Material Supply System on Productivity in Institutional Foodservice (단체급식 회사의 식자재 공급체계 개선에 따른 생산성 분석 연구)

  • Kim, Youn-Tai;Choy, Tae-Ho;Park, Myun-Ae
    • Culinary science and hospitality research
    • /
    • v.10 no.4
    • /
    • pp.133-144
    • /
    • 2004
  • The object of this study was to investigate the effect of food material supply system on productivity in institutional foodservice. This study was examined by food service companies were enlisted under the influence of domestic enterprises, which used central supply system for the central kitchen operation and efficiency food material circulation system. The main result of this study was as follow: According to the analysis of these data, enlargement of efficiency in food utilization was placed at rising of utilization Processing food materials. And resulted in good expectations such as competitive strengthening, quality capacity strengthening and improvement in sanitary conditions from a productivity point of view.

  • PDF

A study on Sustainability Model of Waste Management Using System Dynamics (시스템 다이내믹스를 이용한 페기물관리시스템의 지속가능성 분석모델에 관한 연구)

  • Park, Rhae;Cha, Gun-Ho
    • Korean System Dynamics Review
    • /
    • v.5 no.2
    • /
    • pp.89-123
    • /
    • 2004
  • Using materials recovered from the waste stream instead of virgin resources as a raw material in manufacturing has great environmental and economic benefits. However, there is lack of public interest in needs for integrated waste management and its relevant facilities, because of NIMBY syndrome, This article has proposed a system dynamics model for the study of the potential and systemic consequences of resource circulation management system(RCMS) policy for a Sudokwon landfill site in Korea. The results of the study indicate that the effects of RCMS are seen continuously to increase in term with both the community welfare level and the resource and energy level. Moreover the effects of RCMS appear sharply in the first half of the simulation period.

  • PDF

Diffusion Modelling of Cold Discharge on Coastal waters (연안역의 냉배수 확산모델링)

  • Kim, Jong-Kyu;Kim, Jong-Hwa
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.13 no.2
    • /
    • pp.132-145
    • /
    • 2001
  • The cold discharge from LNG(liquefied natural gas) terminal makes the water temperature around the terminal fall down. This temperature reduction may result in serious changes on marine ecosystem of the coastal area. The numerical model experiments of material transport and tidal circulation in the inner bay, Chinhae Bay are investigated in the dispersion of cold discharge from LNG terminal. The condition of ambient water is exposed to tide, tidal current and cold discharge temperature. Simple numerical model experiments highlight the importance of tidal circulation and cold discharge at each case and some results are discussed. The results of this study can be used as the guideline for the site selection of LNG terminals and long-term marine environmental impact assessment.

  • PDF

Quality Control and Evaluation of Platycodon grandiflorum: Implications for Future Management

  • Xu, Bao-Jun;Zheng, Yi-Nan;Sung, Chang-Keun
    • Natural Product Sciences
    • /
    • v.10 no.4
    • /
    • pp.141-151
    • /
    • 2004
  • Platycodi Radix, as one of the most important traditional oriental materia medica, is utilized frequently in clinical practice and dietary in China, Korea, and Japan. To evaluate definitely the quality of Platycodi Radix, and provide scientific data for commodity circulation, new product development and clinical application of Platycodi Radix, we summarized its medical history, application status, chemical compositions, bioactivities, cultivation, international circulation, quality evaluation, dosage and safety, and brought forward some constructive suggestions on further establishment of international criteria for quality control of Platycodon grandiflorum.

A Study on Eco-village Planning in Chindo-ri, Muju-kun (무주군 진도리의 생태마을 조성계획에 관한 연구)

  • Jang, Won;Kim, Kyong Hwa;Choi, Gui Seon
    • Journal of Environmental Impact Assessment
    • /
    • v.8 no.1
    • /
    • pp.141-146
    • /
    • 1999
  • This paper proposes the planning and design of the Eco-village centering around Chindo-ri, Muju-kun. The Eco-village project has three basic objects the Eco-village residents' lives adapting to ecological principles such as regeneration and circulation, life agricultural techniques based on organic cycle, and residents' harmonious lives with the surrounding nature. For constructing of the Eco-village, first, the subject area was analyzed in terms of the natural and cultural environment and then, on this analytic ground the concrete concept and the specific plan were set up. The following details also should be considered: the scale of the residential household, the population, the space arrangement of the village, the material cycling structure, the waste treatment, the purification of the sewage, the energy supply, the landscape architecture, the production activity, the conservation of the ecosystem and so on.

  • PDF