• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1994.11a
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• pp.67-69
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• 1994

4계절이 뚜렷한 우리나라의 겨울철은 작물생산에 단경기이었으나, 플라스틱 하우스나 유리온실이 보급되면서 겨울철 단경기가 해소되었다. 그러나 이리한 시설들은 PE 또는 유리 등의 피복자재를 사용하여 여름철의 경우 막대한 일사부하로 온실 내부온도가 외부온도보다 높아져 작물생육에 열악한 환경을 조성한다. 이에 fog and pad system, fan and pad system 과 heat pump 등이 개발되어 있으나 실용적으로 도입되지 못하고 있는 실정이다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.11a
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• pp.95-99
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• 1999

자연에너지와 전기에너지를 조합하여 냉방과 난방을 수행할 수 있는 방법중의 하나로 히트펌프 이용기술이 있으며, 국내의 경우 히트펌프는 주로 냉방 또는 냉동을 목적으로 이용되고 있으나, 1980년 이후 전기가 풍부한 경제선진국을 중심으로 난방 또는 냉난방겸용의 히트펌프가 개발되어 주택, 빌딩, 온실 등의 공조시스템에 이용되고 있다. (중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.43-47
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• 1994

화학 열펌프 시스템의 반응기 설계를 위하여 정적 설계의 결과를 이용하여 시간에 따른 전화율, 온도, 압력, 출력 등의 변화에 대한 모사를 시도하였다. 정적 모사를 통한 설계결과는 동적 거동 모사의 결과와 유사하였으며, 이로부터 정적모사가 동적모사를 위한 적절한 초기치와 기초 설계 정보를 제공함을 알 수 있었다. 본 연구를 통하여 확립된 설계절차와 해석방법에 따른 사례연구를 통하여 향후 실용화될 화학 열펌프 시스템의 개략적인 사양과 바람직한 설계방향을 제시 할 수 있었으며, 반응기의 조작에 따른 제어변수의 영향을 평가하는 기준을 마련할 수 있었다.

• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.356-367
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• 2018

A series of tests dedicated to station blackout (SBO) accident scenarios have been recently performed at the $Prim{\ddot{a}}rkreislauf-Versuchsanlage$ (primary coolant loop test facility; PKL) facility in the framework of the OECD/NEA PKL-3 project. These investigations address current safety issues related to beyond design basis accident transients with significant core heat up. This work presents a detailed analysis using the best estimate thermal-hydraulic code TRACE (v5.0 Patch4) of different SBO scenarios conducted at the PKL facility; failures of high- and low-pressure safety injection systems together with steam generator (SG) feedwater supply are considered, thus calling for adequate accident management actions and timely implementation of alternative emergency cooling procedures to prevent core meltdown. The presented analysis evaluates the capability of the applied TRACE model of the PKL facility to correctly capture the sequences of events in the different SBO scenarios, namely the SBO tests H2.1, H2.2 run 1 and H2.2 run 2, including symmetric or asymmetric secondary side depressurization, primary side depressurization, accumulator (ACC) injection in the cold legs and secondary side feeding with mobile pump and/or primary side emergency core coolant injection from the fuel pool cooling pump. This study is focused specifically on the prediction of the core exit temperature, which drives the execution of the most relevant accident management actions. This work presents, in particular, the key improvements made to the TRACE model that helped to improve the code predictions, including the modeling of dynamical heat losses, the nodalization of SGs' heat exchanger tubes and the ACCs. Another relevant aspect of this work is to evaluate how well the model simulations of the three different scenarios qualitatively and quantitatively capture the trends and results exhibited by the actual experiments. For instance, how the number of SGs considered for secondary side depressurization affects the heat transfer from primary side; how the discharge capacity of the pressurizer relief valve affects the dynamics of the transient; how ACC initial pressure and nitrogen release affect the grace time between ACC injection and subsequent core heat up; and how well the alternative feeding modes of the secondary and/or primary side with mobile injection pumps affect core quenching and ensure stable long-term core cooling under controlled boiling conditions.

• Journal of National Security and Military Science
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• s.1
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• pp.423-446
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• 2003

While the demand for energy has shown a sharp increase recently, the supply seems to be limited by the fact that the conventional fossil fuel energy or nuclear energy has its own environmental problems such as, for example, global warming or nuclear waste disposal. To overcome such limited supply of energy, the utilization of natural thermal energy such as river water and seawater as well as treated sewage can be a substantial supplement. The potential use of the unused energy has become more and more feasible these days as the heat pump technology has been advanced. In the present study, the unused energy resources are estimated on regional and monthly basis for each resource by the method proposed here in order to establish the fundamental data for its utilization. The potential use of the unused energy is a1so discussed.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.123.2-123.2
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• 2010

본 논문에서는 2008년 4월 이후 지열원 열펌프가 설치되어지는 현장에 시험공의 지중열전도도를 현장열응답법을 이용하여 측정하였으며, 그간에 측정된 지중열전도도를 이용하여 전국의 지중온도 및 지중열전도도의 산포도를 정리하였다. 지중열교환기의 심도가 150m일 때 지중온도 분포는 약 $12.0{\sim}19^{\circ}C$의 넓은 분포를 보였으나 대부분의 지중온도가 $15.0{\sim}17.0^{\circ}C$의 범위에 분포하였으며, 지중열전도도의 경우도 마찬가지로 1.50 ~ 9.00 W/mk 값으로 아주 넓은 분포를 보였으나 2.30 ~ 2.90W/mk 값이 가장 많이 나타냈다.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.11 no.3
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• pp.1-6
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• 2015

In this study, we analyzed t he design condition for appropriate design factor at geothermal system design documents. It is intended to provide the proper information of geothermal system design condition when construct new building, designer can use design conditions more efficiently. Therefore, it is possible to plan for domestic geothermal system, through utilization at design element, to provide as a good information that can predict the approximate underground condition. Thus, provided the basic design conditions that can predict the capacity of the geothermal system. It will be the first step to solve the problem.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.70-76
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• 2005

It is expected that use of groundwater wells for contaminated groundwater remediation, artificial groundwater recharge and geothermal heat pump systems is increasing in the future in Korea. Some practical confusions may be produced due to lack of regulations related to permits and registrations of these types of wells. This short note is intended to draw attention of relevant professionals by shortly introducing some relevant code of state regulations in Missouri, USA.

• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.591-594
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• 2005

Geothermal energy becomes to be one of the promising energy sources. In this study, technology using water thermal energy from riverbank filtration system(including alluvial and riverbed deposit) is reviewed and checked as an energy resources. The objects of this study are (1) long-term monitoring of alluvial and riverbed sites, (2) preliminary design of cooling and heating system at riverbank filtration facility, and (3) calculation of potential groundwater heat energy, including riverbank filtration system. Measuring data of alluvial and riverbank filtration show slight fluctuations comparing to temperature of atmospheric air which indicates that groundwater obtained from the riverbank filtration system have a sufficient potential as a source of cooling and heating energy.

• Progress in Superconductivity and Cryogenics
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• v.15 no.3
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• pp.49-52
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• 2013

An experiment to investigate the natural circulation of a cryogen has been performed. The study is motivated mainly by our recent development of cryogenic cooling system for prototype superconducting cyclotron without any circulating pump. In the natural circulation loop system, a cooling channel is attached on the outer surface of the aluminium block and the liquid nitrogen passes through inside of the channel to cool the block indirectly. A cryocooler as a heat sink is located at the top to re-condense cryogenic vapor coming from the aluminium block in which electrical heater is installed as a heat source. The main dimensions are determined using the relevant analysis and the natural circulation loop is successfully fabricated. The temperature distributions in the loop are measured during initial cool-down process and in steady state, from which the modified Grashof numbers are calculated and compared with the existing correlation estimated with one-dimensional analysis for steady state flow.