바닥 복사난방시스템에서 PCM 위치에 따른 온도변화 Mock-up 실험

최성호,김성은,송용우,박진철 대한건축학회 2020 대한건축학회논문집 Vol.36 No.10

This study in which a phase change material (PCM) was applied to a general floor heating system, and the temperature change according tothe insertion location was confirmed. Most apartment houses in Korea use a floor heating system using hot water. Since such a floorstructure has difficulty in securing sufficient heat capacity due to structural constraints, it is necessary to develop a new floor heating systemwith improved heat storage performance. Accordingly, the PCM insertion location and heating schedule were introduced and tested in thePCM-applied floor heating system with improved heat storage performance. As a result of the experiment, when the heating was stopped for30 minutes and 3 hours by inserting the PCM into the side, the indoor and surface temperature of Room 2, a floor heating system to whichPCM was applied, was 1.6℃ and 1.5℃ lower than that of Room 1, a general floor heating system. At the time of 1 hour operation and 3hour shutdown, the indoor and surface temperature of Room 2 was 1.0℃ and 0.9℃ lower than that of Room 1. When the PCM wasinserted in the lower part and operated for 30 minutes, the surface and room temperature of Room 2 was 2.4℃ and 1.0℃ higher than thatof Room 1, and 2.4℃ and 1.0℃ higher when operated for 1 hour. According to the experimental results, it was confirmed that in the floorheating system to which the PCM was applied, the surface and room temperatures were higher when the PCM was inserted in the lower partthan in the side of the hot water pipe. 본 논문은 상변화물질(PCM)을 일반 바닥 난방시스템에 적용한 연구로 삽입 위치에 따른 온도변화를 확인하였다. 국내 공동주택은 대부분 온수를 이용한 바닥 난방시스템이 사용되고 있으며, 난방정지시 온도가 저하되는 문제점을 가지고 있다. 이에 따라, 축열성능이 향상된 새로운 바닥난방 시스템의 개발이 필요한 실정이다. Mock-up 실험실을 구축하여 PCM 적용 바닥 난방시스템에 PCM 삽입 위치와 난방 스케줄을 도입하여 실험하였다. 실험결과 PCM을 측면대비 하부에 삽입하였을 경우 표면 및 실내온도가 더 높게 나타났다.

저온잠열저장을 위한 TMA-물계 포접화합물의 과냉각 특성에 대한 연구

김창오(Kim Chang-Oh),김진흥(Kim Jin-Heung),정낙규(Chung Nak-Kyu) 한국태양에너지학회 2006 한국태양에너지학회 학술대회논문집 Vol.- No.-

Ice storage system that water is used as low temperature latent heat storage material, refrigerator capacity is increased and COP is decreased because refrigerator is operated at low temperature due to supercooling of water in the course of phase change from solid to liquid. This study is investigated the cooling characteristics of the TMA-water clathrate compound including TMA(Tri-methyl-amine, (CH₃)₃N) of 20~25 wt% as a low temperature latent heat storage material at -5℃, cooling source temperature. The results showed that the phase change temperature, the specific heat is increased and the supercooling degree is decreased as the weight concentration of TMA became higher. Especially, low temperature latent heat storage material containing TMA 25 wt% has the average of phase change temperature of 5.8℃, supercooling degree of 8.0℃ and specific heat of 4.099kJ/㎏K inthe cooling process. Phase change temperature higher than that of water and inhibitory effect against supercooling can be confirmed through experimental study on cooling characteristics of TMA-water clathrate compound.

포접화합물의 냉각특성에 대한 첨가제의 영향

김진흥,정낙규,김석현,김창오 대한설비공학회 2005 설비공학 논문집 Vol.17 No.2

This study was performed to investigate the phase change temperature, the supercooling, the maintenance time of liquid phase and the change rate of volume of TMA 30 wt% clathrate compound with additives. TMA 30 wt% clathrate compound with additive was cooled at heat source temperature of -6℃. The additives are ethylene glycol and chloroform. Their concentration are 0.1 wt% respectively. The experimental results showed that the phase change temperature was not affected by additives and this was average 5.3℃. Also the supercooling and the maintenance time of liquid phase were decreased by additives. Especially, the average value of supercooling showed by 8.8℃ and the maintenance time of liquid phase was by 19 minutes in the case of chloroform 0.1wt%. Additionally, the average change rate of volume showed by 1.26∼1.31% according to additives and the volume was decreased by the phase change from liquid to solid.

TMA 농도에 따른 저온잠열축열물질의 냉각특성

김창오(Kim Chang-Oh),정현호(Chung Hyun-Ho),정낙규(Chung Nak-Kyu) 대한기계학회 2010 大韓機械學會論文集B Vol.34 No.2

빙축열시스템은 저온잠열저장을 위해 물을 사용한다. 그러나 물은 액체에서 고체로 상변화를 하는 과정에서 물의 과냉각 현상에 의하여 냉동기의 냉동용량 증가와 COP감소의 원인이 되고 있다. 본 연구는 저온잠열축열물질로 적용 가능한 TMA(Tri-methyl-amine, (CH3)3 N) 20~25 wt%를 포함하고 있는 TMA-물계 포접화합물(TMA-water clathrate compound)의 냉각특성에 대한 실험적 연구를 수행하였다. 실험적 연구 결과, TMA 질량농도가 높을수록 상변화온도는 증가하였고, 과냉각도와 비열은 감소하였다. 특히, TMA 25wt%를 포함하고 있는 포접화합물은 냉각과정동안 평균 상변화온도 5.8℃와 과냉각도 8.0℃, 액상유지시간 651sec 및 비열 3.499 kJ/㎏K로서 다른 TMA 농도보다 양호한 냉각특성을 나타내었다. 이와 같이 저온잠열축열물질로서 TMA 25wt%-물계 포접화합물을 적용하는 것이 유리할 것으로 판단된다. The ice storage system uses water for low temperature latent heat storage. However, a refrigerator capacity are increased and COP are decreased due to supercooling of water in the course of phase change from liquid to solid. This study investigates the cooling characteristics of the TMA-water clathrate compound including TMA (Tri-methyl-amine, (CH3)3N) of 20~25 wt% as a low temperature latent heat storage material. The results showed that the phase change temperature are increased and the supercooling degree and the specific heat are decreased according to the weight concentration of TMA increased. Especially, the clathrate compound containing TMA 25wt% has the average phase change temperature of 5.8℃ and the supercooling degree of 8.0℃, retention time of liquid phase for 651sec and specific heat of 3.499 kJ/㎏K in the cooling process. This expressed good than different concentration of TMA cooling characteristic. Like this, to apply TMA 25wt%-water clathrate compound is determined by advantageous as the low temperature latent heat storage material.

알케인류 상변화물질의 열적 특성 해석

崔恩洙,鄭東柱 明知大學校 産業技術硏究所 2003 産業技術硏究所論文集 Vol.22 No.-

Abstract - The objective of the present study is to reveal thermal characteristics of various alkane phase-change-material which have high latent heat during phase change from solid to liquid. In order to analysis thermal characteristics of various phase-change-material, phase-change temperature and energy of various phase-change-material were measured by using differential scanning calorimeter. The phase-change-material slurries which are used in this study were paraffin particle, microcapsulated octadecane and microcapsulated lauric acid. The heating rate of differential scanning calorimeter and the size of phase-change-material were changed during phase-change temperature and energy measurement.

빙축열시스템용 유화용액 축열재의 유동 및 온도특성

김재돌,윤정인 한국건축설비학회 1998 건축 설비 Vol.1 No.3

열에너지를 저장하는 축열 시스템은 공조설비 등에 이용되고 있는 유용한 방법의 하나이다. 이는 여름철 주간 전력의 피크컷(peak cut), 열원기기의 용량 축소, 열원기기 고장시의 대응 등을 목적으로 채용하는 경우가 많으며, 에너지 절약 및 유지비 절감 등의 가능성도 있다. 축열시스템은 크게 현열형(sensible heat type)과 잠열형(latent heat type)으로 나눌 수 있다. 전자는 온도차에 의한 방법으로 냉수, 온수, 건물 구조체, 암석 등이 있으며, 후자는 상변화를 이용한 것으로 얼음이나 잠열 축열재(유치화합물, 파라핀 등)가 여기에 해당된다. 물을 축열재로하는 시스템은 화학적으로 안정하고, 자원이 풍부한 등 여러가지 장점을 가지고 있지만 설비가 커지고, 축열조에서의 열손실이 큰 점 등의 결점이 있다. 한편 빙축열은 물이 얼음으로 상변화할때의 잠열을 이용한 것으로 이 잠열은 현열에 비해 약 80배 정도로 커 적은 체적으로도 효율적인 냉열저장이 가능하다. 또한 축열조의 소형화와 단열의 간편성 때문에 방열손실에 대해 유리하며, 일정온도의 열을 용이하게 이용할 수 있는 장점도 있다. 그러나, 빙축열시스템은 물을 냉각하여 얼음을 생성하는 축냉과정에서 과냉각이 발생하면 일정온도의 열에너지를 고효율로 축적할 수 있는 잠열 축열재로서의 장점을 잃게 된다. 따라서, 본 연구에서는 방축열시스템에 있어 최대의 결점인 과냉각에 의한 냉각온도의 저하로 소요전력의 증가와 얼음의 성장에 따른 열저항의 증대를 극복하기 위한 한 방법으로써 유동성을 가진 얼음의 이용을 고려하였다. 이 방법은 기름, 물, 계면활성제에 의한 다성분 혼합용액을 유화(乳化)냉각하는 것으로 과냉각이나 열저항에 의한 소요전력의 증대를 막을 뿐만 아니라, 혼합유체를 직접 유통시키기 때문에 고효율의 새로운 축열재 개발을 기대할 수 있다. 이와 같은 관점에서 다성분 혼합용액의 냉각에 의한 유동성이 있는 얼음의 생성 및 온도특성에 관한 실험을 통하여 빙축열시스템용 축열재 개발의 가능성을 제시하였다. A fundamental study on ice formation and its temperature characteristics in ice storage system was performed experimentally. In case of ice formation, failing of cooling temperature due to supercooling causes the inereasement of electricity consumption and thermal resistance which restrains the growth of ice. For these reasons, we took the ice with movement into consideration by using the mixture which contains oil, water, and surfactant. From the experimental results, it is possible to make use of the latent heat of mixture because the freezing phenomenon of mixture was almost alike in movement and solidification point maintenance time in comparison with water. Especially, the addition of ethyleneglycol brought the movement into the mixture. On the other hand, this made no use of the latent heat of mixture.

상변화물질을 충전한 기능성 덕트 유닛이 장착된 냉장실 냉각 특성

이석준(Seok-Joon LEE),홍터기(Ter-Ki HONG),박설현(Seul-Hyun PARK) 대한기계학회 2017 대한기계학회 춘추학술대회 Vol.2017 No.11

This paper investigates the temperature characteristics of the refrigerator with functional duct unit filled in a PCM(Phase Change Materials). Although the EPS(Expended Polystyrene) Duct was used in the existing refrigerator, to improve the temperature distribution of the refrigerator, a functional duct unit with PCM was developed and performance tests were conducted. First, In order to analyse the characteristics of PCM, it tested 100ml of water and PCM in the pyrex tube to proceed with the experimental set-up. Second, the experimental equipment was tested using top mounted freezer type 200~300L volume general refrigerator with EPS duct and the same type refrigerator with functional duct unit filled in a PCM. The temperature standard deviations were lower when installing the functional duct unit when installing the EPS duct. Moreover, when installing the functional duct unit, it protects the temperature rise inside the refrigerator during black out.

TMA-물계 포접화합물의 과냉각 개선에 대한 연구

정낙규,김진홍,김창오 朝鮮大學校 機械技術硏究所 2005 機械技術硏究 Vol.8 No.1

This study is investigated the supercooling improvement and the cooling characteristics of the TMA clathrate compound including TMA(Tri-methyl-amine, (CH3)3N) of 25 wt% with additive as a low temperature storage material at -6℃ heat source. The additive is ethanol of 0.1. 0.3 wt% and 0.5 wt%. The results showed that as the concentration of ethanol is increased, phase change temperature, the supercooling and retention time of liquid phase are decreased. Especially, TMA 25 wt% clathrate compound with ethanol of 0.5 wt% has the average of phase change temperature of 3.8℃, supercooling of 0.9℃ and retention time of liquid phase for 6 minutes in the cooling process. From the results of this study, TMA 25 wt% clathrate compound with ethanol showed higher phase change temperature than water and supercooling repression effect.

공동주택 냉방에너지절감을 위한 PCM 축열 건자재의 적정 상변화온도 분석

안상민(An Sang-Min),정창헌(Cheong Chang Heon),황석호(Hwang Suckho),이승복(Leigh Seung-Bok),김태연(Kim Taeyeon) 한국건축친환경설비학회 2010 한국건축친환경설비학회 학술발표대회 논문집 Vol.2010 No.10

The purpose of this study is to evaluate the cooling energy reduction performance of PCM wallboard in apartment buildings by using ESP-r simulation program. A PCM wallboard, which is constructed from the micro-encapsulated phase change materials as a uniform mixture with the conventional gypsum, is applied on the inside wall surfaces in the simulation model. The results show that the application of such materials for lightweight construction makes it possible to reduce fluctuation of inner temperature and energy consumption. Considering cooling load reduction, PCM designed whose solidification temperature close to the cooling set point temperature is appropriate in aparment buildings.

에리스리톨과 만니톨의 혼합물에 대한 융해ㆍ응고 특성

유직수(JikSu YU),호리베 아키히코(Akihiko HORIBE),하루키 나오토(Naoto HARUKI),김명준(MyoungJun KIM) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.11

In this study, in order to use waste heat in middle temperature region (100C-250C) from factories, it is investigated about fundamental melting and solidification characteristic of erythritol, mannitol, and their mixtures as phase change materials (PCMs), which are applicable for latent heat thermal energy system. The melting point of erythritol and mannitol, melting peak temperature of their mixtures, and latent heat were meaured by differential scanning calorimetry (DSC). The melting and solidification behavior of these PCMs put in the test tube was observed by the digital camera. The acquired conclusions are; 1) In the DSC measurement, it was found that at mannitol content from 10 to 30mass% and from 70 to 90mass%, these mixture have one and two melting peak temperature, respectively, and at mannitol content from 50 to 65mass%, it have three melting peak temperature. 2) In fundamental melting behavior of mixtures, it was confirmed that the melting behavior with repeated solidification and melting process does not change, and the density difference of solid phase and liquid phase affects the melting behavior.