• Title/Summary/Keyword: Cool Water

Search Result 222, Processing Time 0.025 seconds

Development of Cooling System for Thermal Management and Water Balance in Fuel Cell Vehicle (연료전지 차량의 열 및 물 균형 유지를 위한 냉각 시스템 개발)

  • Kim, Seong-Kyun;Lee, Seung-Yong;Kim, Chi-Myung;Park, Yong-Sun
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.11a
    • /
    • pp.113-117
    • /
    • 2006
  • This paper Is for development of cooling module in order to maintain heat and water balance in fuel cell vehicle. Thermal management system for fuel cell is disadvantage because the temperature of coolant is lower than that of ICE and heat duty of radiator is higher. By CFD simulation, cool ing module was developed for water balance of system. Hot chamber test and hot area/high altitude test on cool ing module was completed.

  • PDF

Application of Cool Air and Water from an Abandoned Coal Mine on the Induction of Flower Bud Differentiation of Strawberry Plants (폐광의 냉기 및 냉수를 활용한 야냉육묘가 딸기의 화아분화 촉진에 미치는 영향)

  • Kim, Il Seop;Yoo, Keun Chang;Kang, Hwa Seok;Jeong, Cheon Soon
    • Horticultural Science & Technology
    • /
    • v.16 no.1
    • /
    • pp.15-17
    • /
    • 1998
  • In order to provide cool night to strawberry plant with cool air and water, an abandoned cool mine was utilized. It's effects on flower induction and fruit yield in 4 different cultivars were examined. After 70 days of transplanting, flowering frequency was below 65% and 100% in control and treatment of night cooling, respectively and regardless of cultivars. Number of flower buds and flower clusters were higher in treated plants compared with the control. Average time until flowering was much less in treated plants. In terms of yield weight and total yield, 'Suhong' was found to be the best cultivar, averaging 24.2g fruit. Cooling contributed to the 6-7 times of increase in total yield within the frame of harvesting times. The fruit were harvested at 80-97 days after transplanting.

  • PDF

Water Vapor and Thermal Transmission Properties of Hybrid Yarns Fabrics for High Emotional Garments -Water Vapor and Heat Transport according to Experimental-Method- (고감성 의류용 복합사 직물의 수분증기 및 열이동 특성 -실험방법에 따른 수분증기 및 열이동-)

  • Kim, SeungJin;Kim, Hyunah
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.41 no.1
    • /
    • pp.84-97
    • /
    • 2017
  • Water vapor and thermal transmission properties of high emotional garments are important to evaluate wear comfort; in addition, the measuring methods of these properties are also critical for breathable and warm suit fabrics. In this study, the water vapor and thermal properties of composite yarn fabrics made of CoolMax, Tencel, and Bamboo fibers with filaments were measured and compared according to the measuring method. Water Vapor Transmittance (WVT) of the fabric woven by the sheath/core composite yarn in the warp direction was the highest due to the small staple fiber volume in the sheath/core yarn structure and high air voids in the sheath/core yarn fabrics. This property was also the highest in fabrics woven by bamboo staple yarns in the weft direction, and was the lowest on hi-multi filament fabrics. However, water vapor resistance ($R_{ef}$) of these fabrics by KSK ISO 11092 showed the opposite results to the water vapor transmittance method ($CaCl_2$ method); in addition, its correlation coefficient was low. The correlation coefficient between $R_{ef}$ and the drying rate was 0.719; therefore, the measurement mechanism of $R_{ef}$ is analogous to the drying property measurement. The thermal conductivity of the fabrics woven with compact staple yarn showed a high value; however, the hi-multi filament fabric showed low thermal conductivity. Therefore, fiber characteristics affect thermal properties more than yarn structure. The correlation between thermal property and moisture transport was also low. This study showed that: water vapor transmittance was active at the loose yarn structure, dry heat transport was vigorous at the compact yarn structure, and heat transport was affected more by fiber characteristics than yarn structure. In conclusion, sheath/core composite yarns were relevant to the high absorptive cool suit along with siro-fil and CoolMax/Bamboo staple yarns that were relevant to the heat diffusive cool suit.

Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 3: Estimation of Fog Deposition onto Cool-temperate Deciduous Forest by the Inferential Method

  • Katata, Genki;Yamaguchi, Takashi;Sato, Haruna;Watanabe, Yoko;Noguchi, Izumi;Hara, Hiroshi;Nagai, Haruyasu
    • Asian Journal of Atmospheric Environment
    • /
    • v.7 no.1
    • /
    • pp.17-24
    • /
    • 2013
  • Fog deposition onto the cool-temperate deciduous forest around Lake Mashu in northern Japan was estimated by the inferential method using the parameterizations of deposition velocity and liquid water content of fog (LWC). Two parameterizations of fog deposition velocity derived from field experiments in Europe and numerical simulations using a detailed multi-layer atmosphere-vegetation-soil model were tested. The empirical function between horizontal visibility (VIS) and LWC was applied to produce hourly LWC as an input data for the inferential method. Weekly mean LWC computed from VIS had a good correlation with LWC sampled by an active string-fog collector. By considering the enhancement of fog deposition due to the edge effect, fog deposition calculated by the inferential method using two parameterizations of deposition velocity agreed with that computed from throughfall data. The results indicated that the inferential method using the current parameterizations of deposition velocity and LWC can provide a rough estimation of water input due to fog deposition onto cool-temperature deciduous forests. Limitations of current parameterizations of deposition velocity related to wind speed, evaporation loss of rain and fog droplets intercepted by tree canopies, and leaf area index were discussed.

Investigation on the Cooling Characteristics of a Regenerative Evaporation Water Cooler (재생증발식 수냉각기의 냉각성능 해석)

  • Choi Bong-Su;Hong Hi-Ki;Lee Dae-Young
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.18 no.5
    • /
    • pp.393-401
    • /
    • 2006
  • The regenerative evaporation water cooler is devised and analysed in this study. The regenerative evaporation water cooler is composed of a sensible heat exchanger to cool the incoming air, followed by a latent heat exchanger to cool the water evaporatively with the cooled air flowing out of the sensible heat exchanger. By linearizing psychrometric characteristics, the heat and mass transfer in the regenerative evaporation water cooler is analyzed theoretically. The results show that the water can be cooled down even lower than the wet-bulb temperature of the inlet air. When the inlet air is $32^{\circ}C$ and 20% in relative humidity, and the inlet temperature of the water is $20^{\circ}C$, the regenerative evaporation water cooler provides a larger cooling capacity than the conventional evaporation water cooler if the effectiveness of the latent heat exchanger is higher than 0.6 and that of the sensible heat exchanger is higher than 0.5.

Analysis of Flow and Thermal Mixing Responses on Hot Water Discharge by Quencher Devices into an Annular Water pool (원환풀내에서 Quencher Device에 의한 고온수 분출로 일어나는 혼합유동에 관한 연구)

  • Choi, Seong-Seok;Kim, Jong-Bo
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
    • /
    • v.14 no.1
    • /
    • pp.21-30
    • /
    • 1985
  • One of the problems with the Boiling Water Reactor involves the flow and thermal mixings in the suppression water pool high pressure steam discharge into the pool in case of emergency core relief. Varioos heat sensitive devices and pumps for the reactor core cooling are installed in the middle of the suppression pool. Especially the pumps utilize pool water in order to cool the reactor core in emergency cases. In this case, the water temperature for the reactor cool ins should be below a certain temperature specified by the reactor design. In the present investigation, in other to determine the optimum locations of these pumping devices, numerical solutions have been obtained for the model to determine the f low mixing characteristics. Experimental investigations have also been carried out for the flow mixing and for the thermal mixing in the pool during the discharge. Considering that the discharge steam through the Quenching Device becomes hot water immediately in the water pool, the steam- equivalent hot water has been utilized. Examining these characteristices, it becomes possible to deform me the best locations for RCIC, LPCI , HPCI pumps in the suppression water pool for the emermency reactor core cooling.

  • PDF

A Bibliographic Study on the Cause and Symptom of Han-So(寒嗽) (한소(寒嗽)의 원인(原因)과 증상(症狀)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Song, Jin-Oh
    • The Journal of Internal Korean Medicine
    • /
    • v.12 no.1
    • /
    • pp.123-139
    • /
    • 1991
  • This study has been carried out to investigate the cause and symptom of Han-So(寒嗽) by referring to 50 literature. The results were as follows ; 1. The factors causing Han-So(寒嗽) are divided into 3 groups. The 1st inner factors are lung affected by cold(寒傷肺), lung affected by wind and cold, and spleen and lung affected by cold. The 2nd outer factors are body cool, cold water drinking, lung week and cool, spleen week and cool. The 3rd non-inner non-outer factor is the pholegm accumulated. 2. The symptom of Han-so(寒嗽) is as follows ; occlusion of the naris, intolerance to cold, anhydrosis tense pulse, fever, running at the nose, headache.

  • PDF

Effect of Cool Islands on the Thermal Mitigation in Urban Area -Case Study of Taegu Metropolitan City- (대도시에 있어 냉섬의 유형별 온도완화 효과 -대구광역시의 사례 연구-)

  • 박인환;장갑수;김종용;박종화;서동조
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.28 no.1
    • /
    • pp.11-18
    • /
    • 2000
  • Taegu is notorious as hot and dry summer among Korea cities. One of the most important goals of the open space planning is to ameliorate urban climate of the city. The objective of this research is to evaluate the thermal mitigation effect of the cool islands in Taegu metropolitan city. Cool islands of this paper includes parks and rivers surrounded by or adjacent to urbanized areas. Based on the analysis of the thermal band of Landsat TM at May 17, 1997, the thermal mitigation effect of open spaces in the city could be summarized as follows ; Kumho river showed the largest mitigation effect in terms of the width of mitigation zone and temperature difference. Evaporation from wide water surface and evapo-transpiration from riparian grass land could bring into results. Significant mitigation effect of parks covered with forest can be observed. The temperature range of such parks were between 19.05$^{\circ}C$ and 19.44$^{\circ}C$ However, the thermal mitigation effect of Dalsung park and Apsan park was insignificant. The small size and high percentage of hard paving of the former and the relative low density of the residential areas adjacent to the latter could be the main reason. In conclusion, the thermal mitigation effect in urban ope spaces could be detectedby the employment of thermal band data of Landsat TM and GIS buffering technique.

  • PDF

Surface Modification of Flake-Shaped Inorganic Mica and Their Cool Paint Performances (판상형 무기소재인 Mica의 표면개질 및 차열페인트의 특성 평가)

  • Park, Jeong Min;Kim, Hee Jung;Yoo, Jung Whan
    • Applied Chemistry for Engineering
    • /
    • v.27 no.1
    • /
    • pp.35-38
    • /
    • 2016
  • In this study, the mica used as a thermal-insulation material was modified with a silane coupling agent, octyltriethoxysilane (OTES), to improve its hydrophobicity. The modified mica was characterized using FT-IR spectrometer, water wettability test, and water contact angle measurement. The analysis exhibits that OTES for the modified mica sample was well bonded chemically and drastically enhanced the hydrophobicity. The reflectance observed as 73.9% (mica) and 86.4% (OTES/mica), respectively, for OTES/mica was improved about 12.5% before any modifications. Also the modified mica sample showed $7.2^{\circ}C$ decrease in the thermal-insulation performance of cool paints compared to that of using unmodified mica, indicating that the modification of mica with silane coupling agents could be effective in enhancing the thermal-insulation performance of the cool paint.