히트파이프 배열을 갖는 태양열 축열시스템의 열전달 해석

정의국(Jung Eui-Guk),김종규(Kim Jong-Kyu),강용혁(Kang Yong-Heack),부준홍(Boo Joon-Hong) 한국태양에너지학회 2010 한국태양에너지학회 학술대회논문집 Vol.2010 No.4

Heat transfer analysis results were shown for the solar thermal storage system which used heat pipe array. The thermal storage system was composed of thermal storage tank and charging/discharging heat exchanger by connection with the heat pipes. Heat pipe heat exchanger was attached to system, and could carry out charging and discharging to thermal storage tank at the same time. Height of the thermal storage tank was 600 ㎜, and that of the charging/discharging heat exchanger was 400 ㎜. Length of the heat pipe was the same as the total height of thermal storage system, and outer and inner diameter were 25.4 ㎜(O.D.) and 21.4 ㎜(I.D.) respectively. Diameter of the circular was 43 ㎜(O.D.), and fin geometries were considered as the design parameters. High temperature phase change material(PCM), KNO₃ was charged to storage tank to adjust melting temperature. Energy relations between heat exchanger and thermal storage tank were defined by the thermal resistance and node temperature. Physical transient equations of the heat pipe heat exchanger/thermal storage and PCM was modeled with energy conservation. Furthermore, melting/solidification phase change interface radius were calculated based on latent and sensible heat. Thermal storage system sizes satisfying inlet and outlet conditions of the charging/discharging heat exchanger were predicted according to heat pipe fin pitch variation of the thermal storage. Maximum and minimum heat pipe row was predicted to 899 and 808 respectively.

제올라이트를 이용한 화학축열에 대한 실험적 연구

하승호,박정훈,이수헌,김광호 대한설비공학회 2017 설비공학 논문집 Vol.29 No.8

There are three main methods to store heat energy; sensible heat storage, latent heat storage, and thermochemical heat storage. Thermochemical heat storage has the highest storage density among the three methods, so this study focused on the thermochemical heat storage method. Experiments were conducted in this study with Zeolite 13x as thermochemical material in a large-scale reactor with 8 kg of Zeolite 13x. Experiments analyzed storage density of Zeolite 13x with respect to four different heating temperatures (50℃, 100℃, 150℃, 200℃) in heat storage process. As a result, they showed 40~50 percent of storage efficiency in the experiment. Experiments also revealed that reactions between Zeolite 13x and water vapor were reversible and stable, but efficiency of the system was low, compared with sensible heat storage systems or latent heat storage systems.

히트파이프를 사용한 태양열 축열시스템의 성능모사 및 해석

정의국(Jung Eui-Guk),부준홍(Boo Joon-Hong),김종규(Kim Jong-Kyu),강용혁(Kang Yong-Heack) 한국태양에너지학회 2009 한국태양에너지학회 학술대회논문집 Vol.2009 No.11월

Mathematical modeling and performance simulation results were shown for the solar thermal storage system which used heat pipe. The thermal storage system was composed of thermal storage tank and charging/discharging heat exchanger with one by the heat pipes. Heat pipe heat exchanger was attached to system, and could carry out charging and discharging to thermal storage tank at the same time. Height of the thermal storage tank was 600 ㎜, and that of the charging/discharging heat exchanger was 400 ㎜. Length of the heat pipe was the same as the total height of thermal storage system, and outer and inner diameter were 25.4 ㎜(O.D.) and 21.4 ㎜(I.D.) respectively. Diameter of the circular was 43 ㎜(O.D.), and fin geometries were considered as the design parameters. High temperature phase change material(PCM), KNO₃ and low temperature PCM, UNO₃ were charged to storage tank to adjust working temperature. Total size of thermal storage system able to get heat capacity more than 500 ㎾ was calculated and the results were shown in this study. Number of heat pipe was required more than maximum 500, and total length of thermal storage system was calculated to the more than maximum :3 m at various condition.

축열식 열교환기의 축/방열 특성

이동규(Donggyu Lee),정근면(Geunmyon Jeong),강채동(Chaedong Kang) 대한설비공학회 2016 대한설비공학회 학술발표대회논문집 Vol.2016 No.6

Recently, the interest has been increased to the efficient use for unutilized energy and the emission reduction of carbon dioxide. In particular, waste water on middle temperature is recognized to one of the representative unutilized energy, which occurs on manufacturing processes in the many manufacturers such as power, food and textile industry. The unutilized energy have a disadvantage such as the low energy utility because low energy density. Therefore, a lot of research about the system improvement combined with a heat pump were reported for the production of heat energy of high temperature of utility. However, It is important to maintain steadily heat supply from the system. A heat storage and heat exchanger is applied to the system in order to increase utilization because the heated waste water which occurred in the industry process has various flow according to time. In this article, we designed an thermal storage type heat exchanger which has a thermal storage tank and heat exchanger function as an evaporator of heat pump system. The designed thermal storage type heat exchanger has a double shell and tube structure. Moreover, it is structured to the purpose of conducting stored heat and transferring to four heat medium including a phase change material(PCM). In this article, a basic experiment was conducted in order to measure the heat transfer characteristics of the each three heat medium between PCM. And experimental results will be used as the design data for thermal storage type heat exchanger.

폐열온도에 따른 축열식 이중원통다관형 열교환기의 축열 및 방열 특성

정근면(Geun Myon Jeong),김동현(Dong Hyun Kim),이동규(Dong Gyu Lee),정동열(Dong Yeol Chung),백종현(Jong Hyeon Peck),강채동(Chae Dong Kang) 대한설비공학회 2017 대한설비공학회 학술발표대회논문집 Vol.2017 No.6

In recent era, the energy and environmental issues increases the interests, and many researches were undergone to recover unused energy in the form waste heat. This unused energy that occurs mostly from manufacturing processes and power generation industries. The present system is a regenerative evaporator for high temperature waste heat recovery that includes a heat storage tank in a double cylindrical tubular shape heat exchanger having phase change material (PCM), and triple heat transfer is possible. Basic experiments were carried out to confirm the heat storage and release characteristics of the regenerative heat exchanger. As a result of the experiment, we confirmed the change of the temperature and flow rate of the waste heat to the heat storage/release function of the regenerative heat exchanger and the influence on the thermal interference. This experimental result tries to utilize it as the design data of the regenerative evaporator of the high temperature heat pump (HTHP) which generates steam good enough for recovering waste heat.

고온수 온도에 따른 축열식 판형 열교환기의 축/방열 특성

김동현(Donghyun Kim),이동규(Donggyu Lee),강채동(Chaedong Kang) 대한설비공학회 2020 설비공학 논문집 Vol.32 No.10

Heat pump systems for high-temperature steam generation using waste heat generated in industrial sites are attracting attention. However, the disadvantage of waste heat is that it fluctuates quantitatively and qualitatively during the acquisition process. This study proposes the combination of the heat exchanger and thermal storage tank in a high-temperature heat source system to enhance the use of industrial waste heat as an energy source. The developed thermal storage type heat exchanger has a plate type heat exchange structure and allows mutual heat transfer between three mediums, including a phase change material (PCM). Named a thermal storage type plate heat exchanger (TSPHE), it comprises 16 kg of a PCM, with a phase change temperature of 68.8℃ to provide heat storage function. The heat storage and release characteristics of the PCM according to the temperature of hot water and cold water were verified through a heat transfer experiment using the TSPHE. Also, because of the structural characteristics of the TSPHE, the phenomenon of the three-medium heat exchange was verified during the experimental process. The heat storage and heat dissipation characteristics according to the supply temperature conditions of the heat medium used in the TSPHE were analyzed. The results of this study will be used as basic data for applying a thermal storage type evaporator to a high-temperature heat pump that generates steam using industrial waste heat.

심야전력을 이용한 축열식 전기온풍난방과 비축열식 바닥전기패널난방의 난방특성 및 실내온열환경 평가에 관한 연구

최동호,양창남,임홍성 대한건축학회 2003 대한건축학회논문집 Vol.19 No.11

From the viewpoint of the indoor temperature distribution and the indoor comfort of thermal environment, this study investigates the heating characteristics of electric hot air heating system with thermal storage using off-peak electricity and floor electric panel heating system without thermal storage. Considering the effects that the thermal characteristics like the characteristics of thermal storage and time-lag of building structures measured by the heating systems investigated, this study quantitatively estimated the problems to be able to appear during the heating and the degree of the satisfaction on the thermal environment. From this study, it was observed that the electric hot air heating system with thermal storage exhibits more temperature difference between the top and bottom in the space than the floor electric panel heating system without thermal storage. And the former system has advantages that it is more superior in the indoor thermal environment in spite of a little deterioration of indoor temperature at the end of the heating and is more economic than the latter system, and is able to control the deterioration of indoor temperature during off-heating. It was confirmed that the floor electric panel heating system without thermal storage requires a long time to reach the stable indoor temperature after the beginning of the heating, and can keep a constant indoor temperature and improve the indoor comfort.

히트파이프를 이용한 축열식 냉ㆍ난방 시스템에 관한 연구

김성실(Seong-Sil Kim),함성철(Seong-Chol Harm),이양호(Yang-Ho Lee),최병윤(Byoung-Youn Choi) 대한설비공학회 2006 대한설비공학회 학술발표대회논문집 Vol.2006 No.6

The heat pump system is attractive alternatives to conventional heating and cooling systems owing to their higher energy utilization efficiency. The thermal loads of commercial and institutional buildings are generally cooling-dominated. In this study have been developed ice storage type heat pump system for cooling and heating by heat pipe. This system was practiced performance test on evaluation criteria for heat storage systems. Accomplished the actual proof examination and looked into the performance of the system. In this study, measurement and analysis of ice storage type heat pump system for cooling and heating by heat pipe. The heat pump unit COP appears 3.05 for cooling and 4.20 for heating. As a result, the method to energy saving and to using a substitute energy actively that is heat pump cooling & heating system is expected by heat pipe. Thermal storage capacity appears 19.5RTH/㎥ for cooling.

축열식 연소산화장치 구현을 통한 VOCs 산화처리 및 폐열 회수 기술 개발

윤달환,박훈민,정현민,정영훈,민흥기,전동환 사단법인 한국안전문화학회 2022 안전문화연구 Vol.- No.17

The reduction of greenhouse gases and Carbon Neutral (Carbon Zero) due to global warming is agreed by all countries around the world. The increase in global average temperature to climate change is kept within 2°C compared to before industrialization and achieved 1.5°C in the long run. Korea has set a 37% reduction target (315 million tons) compared to the 2030 emission forecast (851 million tons) and is promoting various air pollution reduction technologies and R&D policies to reduce greenhouse gases and minimize the impact on climate change. Currently, there are VOCs that are directly emitted into the atmosphere or that cause greenhouse gases as simple power generation and heat sources. Aromatic hydrocarbons such as benzene are strong carcinogens that cause leukaemia, central nervous disorder, chromosomal abnormalities, and hydrochloride can produce photochemical oxides by destruction of the ozone layer, global warming, and chain reactions of volatile organic compounds, causing eye irritation, reduced visibility, and damage to plants and crops. VOCs reduction technology should reduce the amount of harmful substances in advance by controlling operating conditions and working conditions. Technologies that can effectively process VOCs throughput of 95% or more are heat storage combustion systems and heat storage catalyst combustion systems. This paper proposes a heat delivery system specification design and emission concentration measurement technology for high-efficiency waste heat recovery of 100 CMM RTO (Regenerative Thermal Oxidation) device to reduce air pollution in VOCs generating sites. For the application of the waste heat recovery system, a 100CMM heat storage combustion oxidation system (RTO) is designed, and the performance is evaluated by measuring the concentration of VOC (Volatile Organic Compound) emissions according to production process operating conditions.

充塡層 顯熱 畜熱槽의 性能解析에 관한 硏究

권순석(S.S. Kwon),김시범(S.P. Kim),구본영(B. Y. Koo) 한국해양공학회 1990 韓國海洋工學會誌 Vol.4 No.2

A numerical study on the cylindrical packed bed sensible heat storage unit was accomplished by finite difference method. Relation between the heat storage rate and the mechanical pumping energy and the characteristics of the heat storage were investigated for various inlet velocities and porosities.<br/> In this study, the numerical results are as follows :<br/> 1) The temperature distributions of solid and fluid rapidly reached the steady state as the heat capacity ratio was increased.<br/> 2) The efficiency of the heat storage was increased as the heat capacity ratio was decreased. For constant heat capacity ratio, howover, the efficiency of the heat storage was increased at lower porosity.<br/> 3) It is very profitable to design the heat storage system such that the porosity is larger for the large flow rate and samller for small flow rate.