• 한국농공학회논문집
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• 제56권6호
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• pp.149-158
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• 2014

The effects of spot cooling on growing ever-bearing strawberry in hydroponic cultivation during summer by spot cooling system was estimated in plastic greenhouse located in Pyeongchang. The temperature of cooling water was controlled by heat pump and maintained at the range of $15{\sim}20^{\circ}C$. Cooling pipes were installed in root zone and very close to crown. Spot cooling effect was estimated by applying system in three cases which were cooling root zone, crown plus root zone, and crown only. White low density polyethylene pipe in nominal diameter of 16 mm was installed on crown spot, and Stainless steel flexible pipe in nominal diameter of 15A was installed in root zone. Crown and root zone cooling water circulation was continuously performed at flowrates of 300 ~ 600 L/hr all day long. Strawberry yields by test beds were surveyed from Aug. 1 to Sep. 30. The accumulated yield growth rate compared with a control bed of crown cooling bed was 25 % and that of crown plus root zone cooling bed was 25 % and that of root zone cooling bed was 20 %. The temperatures of root spot in root zone cooling was maintained at $18{\sim}23.0^{\circ}C$ and that of crown spot in crown cooling was maintained at $19{\sim}24^{\circ}C$. Also, the temperatures of root spot in crown plus root zone cooling bed was maintained at $17.0{\sim}22.0^{\circ}C$ and that of crown spot was maintained at $19{\sim}25^{\circ}C$.

• 생물환경조절학회지
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• 제15권4호
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• pp.340-345
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• 2006

A potato (Solanum tuberosum L. cv. Superior) cultivar was grown in aeroponic cultivation system to investigate the effect of root zone cooling in summer. Based on their nutrient uptake, growth responses, and tuberization, the possibilities for potato seed production were determined. Although shoot growth and early tuberization increased in the conventional non-cooling root zone system (root zone temperature of $25\pm2^{\circ}C$), stolen growth, photosynthesis, transpiration rate and number of tubers produced were higher in the cooling root zone system ($20\pm2^{\circ}C$) than in the non-cooling system. Increasing root zone temperature above $25^{\circ}C$ stimulated absorption of K more than T-N, P, Ca, Fe and Mn. On the other hand, root zone temperatures in the range of $20^{\circ}C$ to $25^{\circ}C$ did not affect Mg contents. The lower uptake and supply to leaves of T-N, Fe and Mn at the high root zone temperature promoted early tuberization and advanced haulm senescence. The results stress the importance of keeping root zone temperature to as low as below 20, particularly in summer under temperate Bone.

• 생물환경조절학회지
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• 제11권2호
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• pp.81-87
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• 2002

근권냉방 방식에 따른 냉방 효율과 토마토 생육 특성을 검토하고자 XL냉수순환, 라디에이타 냉풍, 패드냉풍 및 대조구를 처리한 결과는 다음과 같다. 근권부 냉방온도는 공급수온이 17.8$^{\circ}C$일 때 XL 냉수순환구는 18.$0^{\circ}C$ 라디에이타 냉풍구는 27.2$^{\circ}C$, 패드 냉풍구는 20.3$^{\circ}C$였다. 배지 깊이와 시간대별 평균온도는 XL냉수순환구 22.8~24.7$^{\circ}C$. 라디에이타 냉풍구 22.7~24.2$^{\circ}C$, 패드 냉풍구 20.5~23.2$^{\circ}C$, 대조구 25.9~29.6$^{\circ}C$를 나타내어 냉방처리구가 대조구에 비해 5~6$^{\circ}C$더 낮았다. 토마토의 생육에 있어 엽장. 엽폭은 대조구에 비해 컸으며, 생체중 및 건물중의 경우에서도 비슷한 경향이었다 근활력에 있어 대조구는 45.0ug/g에 비해 근권냉방 처리구는 58.5-62.8 ug/g으로 높았으나. 근권냉방 처리구간에는 큰 차이가 없었다.

• 대한기계학회논문집
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• 제16권6호
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• pp.1150-1155
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• 1992

본 연구에서는 제철소 열연공정의 냉각효율 개선을 위한 기초연구로 수행되었 다. 전열면의 초기온도가 900.deg. C이상일 때 층류 냉각방식에 의한 고온강판의 냉각특 성에 영향을 주는 모든 인자를 엄밀히 고려하는 것은 매우 어려운 일이다.따라서 본 연구에서는 노즐과 고온면 사이 거리(L), 유량(Q), 냉각 초기온도 등을 실제 작업 조건에 가깝게 변화시켜 가면서 수냉반경의 변화를 중심으로 전열면의 냉각 특성을 해 석하였다.

• 한국태양에너지학회 논문집
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• 제31권4호
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• pp.1-8
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• 2011

In this paper, inverse building modeling was applied to building perimeter zones which have different window orientation. Two test zones of east-facing and west-facing zones in ERS(Energy Resource Station) building, which is representative of small commercial building, was used to test performance of cooling load calculation and peak cooling load reduction. The dynamic thermal load model for the east and west zone was validated using measured data for the zones and then it was used to investigate the effect of peak cooling load reduction by adjustment of indoor cooling temperature set points during on-peak time period. For the east zone, the peak load can be reduced to about 60% of the peak load for conventional control even without any precooling. For the west zone, PLR is nearly independent of the start of the on-peak period until a start time of 1pm. Furthermore, PLR has a small dependence on the precooling duration. Without any precooling, the peak cooling load can be reduced to about 35% of the peak load associated with conventional control.

• 생물환경조절학회지
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• 제31권4호
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• pp.286-291
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• 2022

본 연구는 근권부 냉방이 토마토 육묘 시 묘 생육에 미치는 영향을 구명하고자 수행되었다. 생장상 하부 파이프 냉방을 이용하여 근권부 온도를 20℃와 25℃로 설정하여 실험을 수행하였다. 전 생육기간동안 초장, 근장, 엽수는 두 온도 처리구간 차이를 보이지 않았다. 엽면적, 지상부와 지하부의 생체중 및 건물중, 엽록소 함량은 파종 28일 경과 시 25℃ 처리구가 더 높았으며, 실험 종료 시 두 처리구 간 유의한 차이를 보이지 않았다. 이상의 결과로 근권부 온도 20℃와 25℃에서 토마토 생육 차이를 확인하지 못했다. 따라서, 본 연구는 고온기 토마토 묘 생산 시 온실 냉방 효율을 높이기 위한 국부 냉방 기술 확립에 도움을 줄 수 있을 것이다.

• 대한설비공학회지:설비저널
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• 제16권3호
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• pp.285-294
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• 1987

Parametric study on the efficiency of Rotary Solid Dehumidifer are reported. Experi-ments have been performed by varying regeneration temperature, regeneration humidity, flow rate of regeneration air, angular velocity of dehumidifer rotor and regeneration angle. To improve the energy efficiency, MODE 2,3 where coding zone is constructed and MODE 4, 5 where recirculating zone is constructed, were studied through experimental method $\ldots$. These results show that economical operating ranges exist in regeneration temperature, flow rate of regeneration air, angular velocity of dehumidifier rotor and regeneration angle. MODE 2,3 where cooling zone is constructed between regeneration Bone and process zone, is far better than MODE 1 in view of energy effiency, and optimum cooling angle and flow rate of cooling air exist. But MODE 4 and MODE 5, where recirculating zone is constructed, are similar to MODE 1.

• 한국추진공학회지
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• 제11권6호
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• pp.9-17
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• 2007

본 연구에서는 램제트 연소실에서의 재순환 유동이 슬롯 막냉각에 미치는 영향에 대하여 실험을 수행하였다. 램제트 연소실 입구의 경사진 확장면 돌출부에 의해 발생된 재순환 유동이 다단 슬롯 중 첫 번째 슬롯에 영향을 미치도록 실험 장치를 구성하여, 슬롯 출구 하류에서의 속도장, 온도장 및 단열 막냉각 효율을 측정하였다. 재순환 유동의 영향에 들어가는 슬롯에서 분사된 냉각유체는 재순환 유동의 높은 전단력과 난류강도로 인해 분사 직후 급격히 주유동과 혼합되어, 재순환 영역에 포함되지 않은 슬롯보다 냉각 성능이 감소함을 결과를 통해 확인하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.59-63
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• 2005

본 연구는 재순환 유동이 램제트 연소실 슬롯 막냉각에 미치는 영향에 대하여 실험을 수행하였다. 경사진 확장면에 설치된 돌출부를 가진 냉각유로에 의해 발생된 재순환 유동이 다단 슬롯 중 첫 번째 슬롯에 영향을 미치도록 실험 장치를 구성하여, 슬롯 출구 하류에서 속도장, 온도장 및 단열 막 냉각 효율을 측정하였다 슬롯을 통해 분사된 냉각유체는 재순환 유동간의 높은 전단력과 난류강도로 인해 분사 직후 급격히 혼합되어, 냉각 성능이 감소함을 결과를 통해 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.2516-2518
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• 2000

In order to reduce the trimming loss for water cooling zone next to finishing block mill in wire rolling, the operational data related to the crop length control of uncooled region was acquired and analyzed. The time deviation of water cooling spray nozzles and the immoderate preset length of uncooled wire rod result in the excessive trimming loss. Therefore, the preset length of uncooled wire rod at each cooling zone are established. The test results of #3 wire rolling mill turned out to be good enough to be expected to increase the ratio of products about 0.15% and establish operational standards of cooling zone.