• Title/Summary/Keyword: heat storage/release

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A Study on the Fire Impact of Adjacent Storage at Outdoor Storage Fire (옥외저장소 화재 시 인접 저장소 화재 영향에 대한 연구)

  • Eun-Ji Kim;Sung-Seek Park;Yong-Han Jeon
    • Journal of the Korea Safety Management & Science
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    • v.26 no.3
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    • pp.93-100
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    • 2024
  • Outdoor storage fires have a significant impact on the surrounding environment, including adjacent storage facilities and buildings. Therefore, it is essential to review and manage the fire impact to minimize damage to human life and property on the outdoor storage fires. In this study, the heat release rate and radiant heat flux were simulated according to the fire time, wind veolcity, and presence or absence of water spray equipment in an outdoor storage facility fire, and the fire impact was analyzed. The outdoor storage was designed to simulate two scenarios on the outdoor storage fires containing gasoline, and FDS was used for fire simulation. As a results, when the water spray facility was not operating and the wind velocity was 5 m/s, the maximum radiant heat flux was 24.80 kW/m2, which exceeded the limit radiant heat flux of 20 kW/m2. When the water spray facility was operating and the wind veolcity was 10 m/s, the maximum radiant heat flux was 18.77 kW/m2, which did not exceed the limit radiant heat flux, indicating that the fire impact on adjacent storage facilities was relatively small.

The Effect of Thermal Storage/Release and Moisture Transport Properties of Polyethylene Glycol-Treated Acrylic Athletic Socks on the Wear Performance (Polyethylene Glycol 처리한 아크릴 운동용 양말의 축열 . 방열성과 수분전달 특성이 착용 성능에 미치는 영향)

  • 조길수;이은주
    • Journal of the Korean Society of Clothing and Textiles
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    • v.19 no.1
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    • pp.36-50
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    • 1995
  • The purpose of this study was 1) to estimate the improvement of thermal storage/release and moisture transport properties of PEG-treated acrylic athletic socks and suggest the optimum add-on for PEG treatment, 2) to investigate wear performance of untreated cocks and two kinds of socks treated with PEG of minimum and optimum add-on respectively, and 3) to consider the effect of thermal storage/release and moisture transport properties of PEG- treated socks on the wear performance and the subjective comfort zone. Thermal activities of specimens treated by PDC were evaluated on a DSC by measuring the heat of fusion on heating and the heat of crystallization on cooling. Moisture regain, absorption speed, wickability, water retenti on value, and water-vapor permeability were measured. In the wear trials that the subjects performed a subsequent exercise protocol wearing three differently treated socks in a conditioned environment ($14\pm2^{\circ}C$, 65$\pm$2% R.H.), microclimate temperature and humidity, and subjective wear sensations including thermal sensation, wettedness, softness, fit, and overall comfort were obtained. PEC-treated specimens with more than 20% add-on showed thermal storage on heating and thermal release on cooling by a DSC and the heat contents of treated ones were generally proportional to the add-ons. Moisture transport properties were highly improved after PEG treatment and increased rapidly with increasing add-on. The tendencies were, however, relaxed above 50% add-on and the treated knits were much stiffer above that add-on. In the wear trials of untreated, PEG add-on 20%, and 50% acrylic socks, the changes of microclimate temperature of 50% socks were significantly less than that of 20% socks. PEG add-on 50% socks showed significantly less changes of microclimate humidity than other two kinds of socks. Three kinds of socks showed significant differences in overall comfort and add-on 50% socks were accepted more comfortable than other two kinds of socks. Comfort zone of foot was extended after PEG treatment on socks and it implied that the subjects wearing PEG- treated socks felt comfortable in wider ranges of microclimate temperature and humidity.

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Shape-Stabilized Phase Change Materials : Frozen Gels From Polypropylene and n-Paraffin for Latent Heat Storage

  • Kim, Jong-Hwan;Ko, Jae-Wang;Son, Tae-Won
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2009.03a
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    • pp.120-121
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    • 2009
  • We prepared polymer-PCM gels such as prepared frozen gel from polypropylene and n-Paraffin for thermal storage and release materials, their basic properties and possible applications especially in latent heat storage. The preparation methods are used to melting method and absorption method respectively. The composition and properties of prepared frozen gels from polypropylene and n-Paraffin were observed by DSC, FT-IR spectra, ARES and Elemental analysis. We can prepare frozen gels in different temperature for latent heat storage materials as controlling composition of phase change material as well as using different incorporating phase change materials. These frozen gels can be used to latent heat storage materials for several applications.

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A Study on the Thermal Characteristics of a $MgO/H_2O$ Chemical Heat Pump ($MgO/H_2O$ 계 화학식 열펌프의 열적 특성에 관한 연구)

  • ;;;;Yukitaka Kato
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.1
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    • pp.34-41
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    • 2004
  • The chemical heat pump based on the Dehydration/Hydration process with a MgO/$H_2O$ system has been researched. The reactor bed could be expected to store the heat around 200∼37$0^{\circ}C$ by the dehydration reaction and to release the heat around 100∼16$0^{\circ}C$ by the hydration reaction under the heat amplification mode operation. The heat output rate of the heat pump system was evaluated using the experimentally determined parameters. The results show that 6∼50 W/kg of heat output and 0.5∼0.8 of heat recovery ratio are attainable. The heat pump will be applicable for a load leveling in a co-generation system by chemical storage of surplus heat at low heat demand and by supplying heat in the peak load period.

Heat Transfer Characteristics of High Temperature molten salt storage for Solar Thermal Power Generation (태양열 발전을 위한 고온 축열 물질의 열전달 특성)

  • Aiming, Mao;KIm, Ki-Man;Han, Gui-Young;Seo, Tae-Beom;Kang, Yong-Heack
    • Journal of the Korean Solar Energy Society
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    • v.27 no.3
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    • pp.63-69
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    • 2007
  • The heat transfer characteristics of inorganic salt for high temperature heat storage material of solar power system were examined. The inorganic salts employed in this study was a mixture of $NaNO_3$ and $KNO_3$ and the operating temperature range was determined by measuring the melting temperature with DSC and by measuring the thermal decomposition temperature with TGA. The heat transfer characteristics was qualitatively obtained in terms of temperature profiles of salt in the tanks during the heat storage and heat release process as a function of steam flow rates, steam inlet temperature and the inlet position of steam. The effects of steam flow rates and inlet temperature of steam were experimentally determined and the effect of natural convection was observed due to significant density difference with temperature.

Study on the Characteristics of Hydrogen Storage according to the Structure of Storage Tank using Metal Hydride (수소저장합금을 이용한 수소저장탱크의 구조에 따른 수소저장 특성 연구)

  • Sim, Kyu-Sung;Myung, Kwang-Sik;Kim, Jung-Duk;Kim, Jong-Won
    • Journal of Hydrogen and New Energy
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    • v.13 no.1
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    • pp.90-99
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    • 2002
  • In order to utilize hydrogen energy in a large-scale in the future, development of effective hydrogen storage method is essentially required as well as that of efficient hydrogen production method. The hydrogen storage method using metal hydrides has been holding the spotlight as a safer and higher-density hydrogen storage method than conventional hydrogen storage methods such as liquid hydrogen or compressed hydrogen storage method. However when metals react with hydrogen to store hydrogen as metal hydrides, they undergo exothermic reactions, while metal hydrides evolve hydrogen by endothermic reaction. Therefore, hydrogen storage tank should have such structure that it can absorb or release reaction heat rapidly and efficiently. In this study, a review on the improvement of the heat release and absorption structure in the hydrogen storage tank was conducted, and as a result, a new type of hydrogen storage tank with the structure of vertical-type wall was designed and manufactured. Experimental results showed that this new type of tank could be used as an efficient hydrogen storage tank because its structure is simpler and manufacture is easier than cup-type hydrogen storage tank with the structure of packed horizontal cup.

Rate Augmentation of Exothermic Hydration in the CaO Packed Bed (CaO 충전층의 수화발열반응 촉진)

  • Chung, Soo-Yull;Kim, Jong-Shik
    • Solar Energy
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    • v.14 no.2
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    • pp.91-101
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    • 1994
  • Heat release characteristics of a CaO packed bed reactor which is used for a chemical heat storage device has been studied. We employed Cu-plate fins to release the heat of reaction of the CaO packed bed inside the reactor fast and effectively. Two-dimensional analysis of unsteady state heat flow inside the bed was performed as a function of time and under various conditions of the Cu-plates. It is noted that the time required to release the heat of reaction with Cu fins is reduced more than twice fast compared to that without Cu fins. That was largely dependent upon the number of Cu-plate, as well.

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Experiments on Operation Characteristics of In-Water Harvest-Type Ice Storage System (수중 하베스트형 빙축열 시스템의 운전특성 실험)

  • Choe, In-Su;Kim, Jae-Dol;Yun, Jeong-In
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.5
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    • pp.653-659
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    • 2001
  • This paper is concerned with the development of a new method for making and separating ice in-water and saving floated ice by installing an evaporation panel in an ice storage tank. The new method shows very good heat transfer efficiency than that of the convectional method. It is because the evaporation panel is directly contacted with water in the storage tank. The experiments were performed by varying inlet and outlet refrigerant temperatures of its evaporator. From the experimental results, the operating characteristics of in-water harvest-type ice storage system were investigated by measuring temperature and pressure at each point of the ice storage system and power required to operating compressor respect to the changes of the inlet and outlet refrigerant temperature of evaporator. It can be think that defrost frequency decreased and heavy ice created as the refrigerant temperature of evaporator outlet and defrost setting temperature is low so gotten result can effect to release efficiency. Also, consumption power, condensing heat quantity, refrigerating capacity and performance efficiency decreased as time goes by. Therefore, these results provide the basic data for system optimization, performance improvement and the possibility of application to other fields.

An Approach to Improve Thermal Insulation Properties and Fabric Hand of Wool and Wool-like Fabrics under High Molecular Polyethylene Glycol Treatment (고분자량 Polyethylene Glycol 처리에 따른 모직물과 유사모직물의 보온성과 태의 향상 방안 모색)

  • 조길수;이은주
    • Journal of the Korean Society of Clothing and Textiles
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    • v.21 no.6
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    • pp.1041-1050
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    • 1997
  • This study was carried out to improve the thermal insulation properties of wool and wool- like fabrics by treating the fabrics with polyethylene glycol, to evaluate the fabric hand of PEG treated wool and wool-like fabrics and to grade up the fabric hand of the treated fabrics by treating with softening agents. Wool and wool-like fabrics were treated with high molecular PEG-8,000 by PDC. The thermal release/storage properties were measured on a DSC. Hand of specimens were evaluated by KES-FB system. The results were as follows; 1. PEG-treated fabrics showed thermal storage and thermal release properties by DSC and the heat contents were generally proportional to the add-ons. 2. PEG-treated fabrics showed higher Koshi and lower Numeri and Sofutosa values due to lower tensile energy and recovery and higher bending rigidity and shear stiffness as the add- ons increased. 3. PEG-treated fabrics showed much lower bending rigidity after softening agents treatment.

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