• Title/Summary/Keyword: 건구온도

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Experiment study on Heating Performance of Heat-pump chiller (실외온습도 변화에 따른 히트펌프 칠러의 난방성능에 관한 실험적 연구)

  • Lee, Kwon-Jae;Lee, Sang-Jae;Kim, Jung-Seok;Lee, Soo-Kwang;Park, Kyoung-Man
    • Proceedings of the KAIS Fall Conference
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    • 2010.05b
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    • pp.1123-1126
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    • 2010
  • 본 연구에서는 외기온습도에 따른 히트펌프 칠러의 난방성능을 조사하고자 하였다. 난방표준 온도조건에서 건구온도 및 습구온도 변화에 따른 히트펌프 칠러의 난방능력과 COP를 획득하기 위하여 항온항습 챔버와 항온수조를 사용하였다. 실험은 건구온도 $7^{\circ}C{\sim}17^{\circ}C$, 상대습도 67%~87%에서 수행하였다. 외기온도가 증가함에 따라 난방능력은 약 27%, COP는 약 28% 증가하였지만, 상대습도 증가에 따른 난방능력과 COP의 변화는 거의 없었다. 따라서 난방운전 시 건구온도의 영향은 크고, 상대습도의 영향은 미미함을 알 수 있었다.

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Effectiveness of the Aluminum Thermal Screens Depending on the Allocation Type (알루미늄반사재의 배치형태에 따른 보온 효과)

  • Kim, Young-Bok;Park, Joong-Choon;Huh, Moo-Ryong;Lee, Si-Young;Jeong, Sung-Woo
    • Journal of Bio-Environment Control
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    • v.16 no.4
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    • pp.284-290
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    • 2007
  • Thermal insulation effectiveness of the aluminum insulator depending on the direction of its glossing face, number of layer and allocation position was investigated. Modules were assembled by the combination of the variables levels and experimented for the case of 100 W and 40 W heating in the modules. The temperatures in the modules with the aluminum insulator were higher than those of the modules with polyester curtains. For the modules with one layer aluminum insulator, the inside temperatures of the modules with the direction of the glossing face outward were higher than those of the modules of inward. For two layer of aluminum insulator, the directions of those glossing faces were recommended to be the same direction for higher thermal insulation effectiveness. For the modules without heating, the temperature difference between the modules were not significant. The black globe temperatures in the modules were changed with the similar tendencies with the dry bulb temperatures in the modules. Those of the black globes were higher than those of the dry bulb temperatures as a whole. It was more distinguished for the modules of inward direction.

Analysis of Cooling Effect on the Plastic Film Cover of Greenhouse Module Depending on the Shade and Water Curtain (온실지붕 차광과 수막 수준에 따른 냉방효과 분석)

  • Kim, Young-Bok;Park, Joong-Chun;Lee, Seung-Kyu;Kim, Sung-Tae;La, Woo-Jung;Huh, Moo-Ryong;Jeong, Sung-Woo
    • Journal of Bio-Environment Control
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    • v.15 no.4
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    • pp.306-316
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    • 2006
  • In this study, the effect of the shade level, water flow rate applied to the shades and the temperature of water on the greenhouse cooling was investigated depending on the shade level of 0, 35, 55, 75%, and water flow rate and water temperature by the test on the small wooden frames to find out the low cost cooling method. With increasing of the dry bulb temperature of outside air, the dry bulb temperature in the wooden frames increased. For the frames with the shade and water, inside temperatures of the frames were lower of -0.2$\sim$-1.2$^{\circ}C$ than the temperature of the outside air and higher than the water temperature. For the frames without water, inside temperatures of the frames were higher of 1.7$\sim$4$^{\circ}C$ than the outside and not affected by the shade level very much. The water flow rate and the temperature of the water were not the important factors to decrease the inside temperatures in the frames. The black globe temperature became lower with increasing of shade level. The shade frames with water curtain showed the best cooling effect because of reducing thermal radiation and cooling the plastic film cover. The surface temperatures of the plastic film cover for the water supplied modules became lower with increasing of the shade level. The relative humidity was decreased with the dry bulb temperature in the frame increasing and not affected by the dry bulb temperature of the outside air for the frames with the shade and water.

Distribution and Correlation of the Dry Bulb Temperature in Anmadang of Korean Traditional House (한옥 안마당의 계절별 건구온도 분포 및 상관도에 관한 연구)

  • 이주동;박현장;공성훈;이중우
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.6
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    • pp.489-494
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    • 2003
  • "Anmadang" of traditional Korean house is an empty space, surrounded by buildings shaped like the letter, ‘ㅁ’.‘ㅁ’shaped traditional Korean house provides much more comfortable outdoor space for various activities than ‘ㅡ’shaped traditional Korean house. In this paper it has been tried to analyse the dry bulb temperature condition of indoor and outdoor space through measurement of dry bulb temperature in Anmadang, Maru and outdoor space. This paper also analyses the correlation of dry bulb temperature between Anmadang and outdoor space with seasonal variations in traditional Korean houses.

The Effects of Drying Schedules on the Bending Properties of Lodgepole Pine Dimension Lumber Treated with CCA (건조 Schedule이 CCA 처리 Lodgepole Pine 각재의 휨강도 성질에 미치는 영향)

  • Kim, Gyu-Hyeok
    • Journal of the Korean Wood Science and Technology
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    • v.19 no.2
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    • pp.65-71
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    • 1991
  • 본 연구는 CCA 처리재의 재건조(再乾燥)시 적용된 건조 스케쥴 (통상(通常) 열기건조(熱氣乾燥)와 고온건조(高溫乾燥) 스케쥴)이 처리재의 휨강도(强度) 성질에 미치는 영향을 고찰하고자 수행되었다. 탄성계수(彈性係數)(MOE), 그리고 비파괴시험(非破壞試驗)에 의해 얻어진 동적(動的) 탄성계수 (Dynamic MOE) 및 대수감쇠율(對數減衰率)(Logarithmic decrement) 은 처리후 재건조에 의해 큰 영향을 받지 않았다. 반면에 적용된 건조 스케쥴에 관계없이 재건조시 심각한 파괴계수(破壞係數)(MOR)의 감소가 파괴계수 분포의 모든 영역에서 초래되었다. 그러나 통상 열기건조(최대 건구온도=$71^{\circ}C$)와 고온건조(건구온도=$110^{\circ}C$) 서로간에는 감소의 정도에 큰 차이가 없었다. 따라서, 처리재의 재건조사 심각한 파괴계수의 감소가 용인(容認)되지 않는다면 CCA로 처리된 Lodgepole pine 각재의 재건조는 미국 연방 임산물 시험장의 Lodgepole pine의 통상 열기건조 스케쥴 (T9-C3) 보다 온화(溫和)한 조건으로 실시되어야 할 것이다.

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Study on Control of Thermal Environmental Factors for Improvement of Productivity of Laying Hens in Summer (여름철 산란계사 내 열환경인자 중 제어요소에 관한 연구)

  • Kim, Seong-Wan;Lee, Tae-Hoon;Cha, Gwang-Jun;Gutierrez, Winson M.;Chang, Hong-Hee
    • Journal of agriculture & life science
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    • v.53 no.2
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    • pp.121-129
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    • 2019
  • This study carried out to determine control factors for the improvement of productivity of laying hens suffering heat stress during hot weather. A total of 48,451 ISA Brown layers were housed in a farm located in Gyeongsangnam-do, Republic of Korea. Five thermo-hydrometer loggers were installed inside the house to collect data of dry-bulb temperature and relative humidity. The experiment continued for 81 days when the summer season begins from 19th June to 7th September, 2018. This study analyzed the correlations among layers' production index and daily average, highest, and lowest temperature; daily average, highest, and lowest relative humidity; and daily average, minimum, and maximum THI. The result indicated that feed consumption, hen-day egg production, egg weight, and FCR decreased as the daily average, highest and lowest dry-bulb temperature and THI rise (p<0.01). On the other hand, water intake increased as the daily average, highest and lowest dry-bulb temperature and THI rise (p<0.001). The relative humidity was not considered to have direct correlations to the layers' production index (p>0.05). However, it was noticeable that the mortality did not have significant relations with daily average and highest temperature; THI; or daily average, highest and lowest relative humidity while it was relevant to the daily lowest temperature and THI (p<0.05). In conclusion, to enhance the productivity of laying hens in a hot climate, it is recommended that daily average, highest, and lowest dry-bulb temperature and THI are maintained as low as possible. Especially, the daily lowest temperature is needed to lower to 20℃, which is the lowest critical temperature for layers.

Studies on the Wet-injury Resistance of Wheat and Barley Varieties III. Effect of Various Moisture Levels on the Top and Root Growth of Barley Crop (맥류 내습성에 관한 연구)

  • Hyung-Soo Suh
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.22 no.2
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    • pp.80-92
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    • 1977
  • This experiment investigated the effect of various moisture levels on the top and root growth of barley and its yield. Resistant varieties to excess moisture injury shortened plant height, but tillered more, having creeping plant type compared with ordinary one, and greater portion of root of this varieties occured at the deeper soil depths with longer root length. However, susceptible one to excess moisture injury showed an inversed trend when compared with the untreated one. Oversaturated treatment compared with the untreated increased a little bit soil temperature and Eh of soil. Increased root activity and increased yield were obtained with resistant varieties compared with the untreated. Lower root activity and less yield than those of the untreated were observed in both extreme treatments. Yield reduction in both the extreme treatments was mainly due to reduction of tiller number, grain number and 1, 000-grain weight. Highest yield reduction was marked at the stage of internode elongation in the oversaturated and at the booting stage in the overdried treatment.

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Desiccant Dehumidifier Selection Program (데시칸트제습기 선정프로그램)

  • Kim, Hue-Jae;Park, Seung-Tae;You, Kyoung-Rok;Lee, Hyun-Ju
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.224-229
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    • 2009
  • Performance curve of the desiccant rotor is an important information when developing and selecting the desiccant dehumidifier. The effective utilization of the energy is major capacity for the system and the desiccant performance curve is a design ability for a designer. By the rotor supply contract with DRI, ECO-DRY programs would be offered. Moreover, it could make remarkable progress in the desiccant system and energy saving. It is good to introduce the programs with the amicable help of DRI.

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The effect of solar shading height on thermal environment for the cultivation of plants in Daegu region (태양열 가리개가 설치된 대구지방의 작물시설에서 가리개 높이에 따른 온열 조건의 변화에 관한 연구)

  • Kong, Sung-Hoon;Lee, Jong-Kuk
    • Journal of the Korean Solar Energy Society
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    • v.25 no.2
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    • pp.45-51
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    • 2005
  • The solar shading height for the cultivation of plants is a very important factor because it has an effect on the variations of the solar energy. In this study, the solar shadings were built in Daegu region to investigate the optimum thermal conditions for the cultivation of plants and to provide the basic data. The thermal environment factors (dry bulb temperature, relative humidity, air velocity) were then measured and analyzed. It is found that the heights of the solar shadings have an uniform effect on the thermal environment for the cultivation of plants: the higher the heights of the solar shadings the higher temperature was obtained. But surprisingly this trend was not found for the relative humidity and the air velocity.