• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.11a
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• pp.100-103
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• 1999

온풍난방은 우리 나라 대부분의 온실난방지역에서 가장 많이 채택하고 있는 온실난방방법으로 간주되고 있다. 온풍난방은 기본적으로 화석연료를 연소열로 변환시켜 온실난방에 사용하는 방법으로 온수난방, 태양열난방 보다 열효율이 높다. 가장 보편적 온실난방열원으로는 경유나 보일러등유를 연소실에서 연소하여 열교환기를 거친 후 온풍기의 상부에 부착되어 있는 송풍팬으로 강제적으로 온실 내로 온풍을 불어넣는다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.39-44
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• 1998

현재 국내에 보급되어 있는 현대화 온실 203개를 대상으로 냉난방과 관련된 설비현황을 조사하여 분석한 결과를 요약하면 다음과 같다. \circled1 온실의 건설방위는 남북동(58.1%)과 동서동(26.8%)이 대부분이었고, 철골온실은 Wide-span형이 81.8%, 플라스틱온실은 1-2W형 온실이 97.5%였다. 휴작하는 온실은 약 41%정도였고, 재배작물은 채소류가 약 80%, 화훼류가 약 20%정도였으며, 재배방식은 철골온실의 경우 양액재배가 57.2%, 플라스틱온실에서는 토양재배가 88.5%였다. \circled2 온실의 외부 피복재는 철골온실은 유리가 92.2%, 플라스틱온실에서는 PE가 43.3%, EVA가 51.9%로 대부분이었다. 철골온실은 1중피복이 98.7%로 거의 전부이었고, 플라스틱온실에서는 2중피복이 78.7%로 나타나, 철골온실에서 보온커튼을 통한 보온성 향상과 밀폐성이 더욱 중요함을 알 수 있다. \circled3 보온용 피복재는 부직포가 64.9%로 가장 많았고 대부분 2층커튼(85.9%)이었으며, 개폐방식은 대부분 예인식(92.7%)의 자동개폐방식(75.2%)이었다. 한편 바닥을 피복한 온실은 약 30% 정도로 나타나, 바닥피복으로 인한 축열이나 반사효과를 감안할 때 효율적인 바닥처리가 요망된다. \circled4 온실의 난방방식은 철골온실에서는 온수안방(47.3%)이 온풍난방(33.8%)보다 다소 많았으며, 플라스틱온실에서는 대부분 온풍난방(90.8%)이었다. 온실의 난방위치는 대부분 지상난방(89.8%)이었고 지중난방은 극소수로 나타나, 앞으로 지중난방을 통한 난방비 절감과 품질향상에 관한 실용화 연구가 요망된다. 난방용 연료는 대부분 경유(83.9%)로 나타나, 난방비를 절감할 수 있는 저가의 연료를 사용할 수 있는 난방시스템의 개발이 요청된다. \circled5 온실의 냉방방법은 차광(51.8%)과 지붕살수(33.9%)가 대부분이었으며 미스트와 포그시스템을 설치한 온실은 소수에 불과하였고, 극소수의 온실에서는 지붕위나 온실내에 지붕면과 평행하게 설치한 경우도 있었다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.29-30
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• 2001

자연에너지원중 태양에너지를 이용한 자갈축열 태양열 온실의 난방에너지 절감효과를 분석하기 위하여 야간에 내부설정온도를 18℃로 했을 때의 자갈축열 태양열 온실과 동일한 제원의 대조온실의 난방연료소비량을 비교하였다. 자갈축열 태양열 온실의 경우 난방초기에는 연료가 대조온실에 비해 약 10%정도 더 소모되었으나 2일이 경과한 후에는 점차 난방연료소비량이 감소하였다(Fig. 2) 이러한 결과는 자갈축열 태양열 온실의 경우 주간에 온실에 투여되는 일사에 의해 축열이 이루어 질뿐만 아니라 야간에 난방을 할 경우에도 축열층의 온도가 설정온도에 도달할 때까지 축열이 이루지기 때문인 것으로 분석되었다 (Fig. 1). 3월 10일부터 3월 15일까지 6일간의 난방연료소비량이 대조온실은 167℃였으나, 자갈축열 태양열 온실은 109℃로써 대조온실에 비해 약 35%정도 난방연료 절감효과가 있는 것으로 분석되었다(Fig. 2). 6일간의 난방 후 자갈축열 태양열 온실에 난방을 중단한 결과 온실외부의 최저기온이 -2.4℃일 때 자갈축열 태양열 온실의 내부최저온도는 14℃를 유지하였으며, 이후 계속 난방을 수행하지 않은 상태에서도 주간에 축열효과로 인하여 최저외기온이 3℃전후일 때 자갈축열 태양열 온실의 내부온도는 15℃를 유지하였으나 대조온실은 5℃ 전후였다. 그리고, 일기온차가 심한 3월말에는 야간설정온도가 18℃인 경우에 자갈축열 태양열 온실의 난방연료소비량이 대조온실에 비해 월등히 적음을 알 수 있었다(Fig. 1, 2). 3월에 자갈축열 태양열 온실의 난방연료소비량은 대조온실에 비해 약 50%이상의 절감효과가 있는 것으로 나타났다./TEX>3.1cm, 2cm$\times$4.2cm 순으로 나타났다. 5. 저고리의 옆길이 곡선에 대한 평가는 진종의 중심인 겨드랑이가 5cm인 것이 가장 우수한 것으로 나타났으며, 그 다음으로 4cm, 6cm, 3cm 순으로 나타났다. 6. 이에 위의 항목들을 종합하여 제작한 연구저고리는 등길이가 28cm, 어깨선 위치는 1.75cm, 깃크기는 5cm$\times$21.5cm, 소매통 크기는 3cm$\times$4.3cm, 옆길이 곡선은 5cm로써 그 형태에 따른 신체적합성에 대한 외관 관능검사 결과로 3.83의 평균값으로 나타났고, 심미성에 대한 외관 관능검사를 항목별 평균치 값으로 종합하면 4.00의 값으로 나타났다. 또한 각 부위별 동작적합성 관능검사는 7가지 동작을 부위별 항목 평균치 결과 3.95의 유수한 저고리로 평가되었다. 본 연구 실험 결과 앞으로도 전통 저고리를 피복함에 있어 외관과 동작적합성이 좋은 저고리를 만들기 위해 지속적 연구가 요청된다. turned back than the Korean women's. Based on the above findings, a torso prototype was developed for the Chinese women by setting the body measurements in reference with their average body measurements plus minimum reserve. The reference lines were set for front/back central line, front/

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.324-332
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• 2017

The comparative experiments were conducted for single span greenhouses where cucumbers were cultivated to analyze the effect of heating between a carbon fiber electric heating element heater and an oil hot air heater in terms of the inside climate, energy consumption and plant growth. In order to analyze the effect of heating capacity, 6, 9, and 16 kW of electric powers were supplied to the electric heating element for same setting temperature of 15?. As a result, as the heating capacity increased, the number of ON-OFF cycles of the electric heating element and the temperature inside the greenhouse increased proportionally. In the comparison of two heaters, it was shown that the temperature and relative humidity distributions of the electric heating element installed greenhouse was much uniform than those of the oil hot air heater installed greenhouse. The heating energy consumptions during the heating period of 79 days were 867L for the oil hot air heater and 8,959 kWh for the electric heating element heater, and the heating costs were 607 and 403 thousand won respectively. In the electric heating element installed greenhouse, the cucumber growth was slightly better and the yield was 4.3% higher than those of the oil hot air heater installed greenhouse, but there were no statically significant difference in the cucumber growth and yield between greenhouses.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.225-231
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• 2016

Glasshouse heating package technologies to improve energy usage efficiency in winter were developed. Heating package was composed of the ground water source heat pump with heating capacity of 105kW, the aluminum multi-layer thermal curtain with six layers of different materials and the root zone local heater with XL pipes of ${\phi}20mm$. Venlo type glasshouse($461m^2$) with the heating package was compared with the same type and area control glasshouse with the light oil boiler, the usual non-woven fabric thermal curtain with respect to the glasshouse inside temperature, relative humidity, crop growth, and heating energy consumption. The results of test in paprika cultivation glasshouses showed that the air temperature inside glasshouse with aluminum multi-layer thermal curtain was maintained $2.2^{\circ}C$ higher than that of control glasshouse in un-heating night time and the temperature in bed with root zone local heating was $4.7^{\circ}C$ higher than that in bed without local heating. Average heating coefficient of performance(COP) of the ground water source heat pump used in paprika cultivation was 3.7 and the glasshouse inside temperature was maintained at $21^{\circ}C$ of heating set up temperature. The heating energy consumptions per 10a were measured at 14,071L of light oil and 364kWh of electric power for the control glasshouse and 35,082kWh for the glasshouse applied heating package. As results, the heating cost of the glasshouse applied heating package was 87 percent lower than that of control glasshouse. The growths of paprika in glasshouses of control and applied heating package did not show any significant difference.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.07a
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• pp.310-315
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• 2002

겨울철 저온기에 온실의 작물재배는 많은 에너지가 소요되어 저온기의 에너지비용을 최소화하는 것이 온실의 운전비용의 절감과 이용효율이 증대되어 농가소득을 높일 수 있다. 저온기에는 작물의 수확량이 적정 온도조건의 80%수준으로 최소 에너지 투입방법 기술을 개발하여 수확량을 증대시킬 필요가 있다. 기존의 난방방법인 온수보일러는 온도유지 안정성은 좋으나 시설비용이 많이 들고 온풍난방은 설치비용은 저렴하나 온도 유지안정성이 다소 떨어지는 단점이 있다. (중략)

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.335-341
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• 2019

In order to provide basic data for uniformization of temperature distribution in heating greenhouses, heating experiments were performed in two greenhouses with a hot water heating system. By analyzing heat transfer characteristics and improving pipes layout, measures to reduce the variation of pipe surface temperature and to improve the uniformity were derived. As a result of analyzing the temperature distributions of two different greenhouses and examining the maximum deviation and uniformity, it was found that the temperature deviation of greenhouses with a large amount of hot water flow and a short heating pipe was small and the uniformity was high. And it was confirmed that the temperature deviation was reduced and the uniformity was improved when the circulating fan was operated. The correlation between the surface temperature of the heating pipe and the indoor air temperature was a positive correlation and statistically significant(p<0.01) in both greenhouses. It was confirmed that the indoor temperature distribution in a hot water heating greenhouse was influenced by the surface temperature distribution of heating pipe, and the uniformity of indoor temperature distribution could be improved by arranging the heating pipe to minimize the temperature deviation. Analysis of the heat transfer characteristics of heating pipe showed that the temperature deviation increased as the pipe length became longer and the temperature deviation became smaller as the flow rate in pipe increased. Therefore, it was considered that the temperature distribution and the uniformity of environment in a greenhouse could be improved by arranging the heating pipe to shorten the length and controlling the flow velocity in pipe. In order to control the temperature deviation of one branch pipe within $3^{\circ}C$ in the tube rail type hot water heating system most used in domestic greenhouses, when the flow velocity in the pipe is 0.2, 0.4, 0.6, 0.8, $1.0m{\cdot}s^{-1}$, the length of a heating pipe should be limited to 40, 80, 120, 160, 200m, respectively.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1992.12a
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• pp.21-22
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• 1992

온실의 난방에 필요한 난방기기의 용량 및 연료소비량을 합리적으로 추정하기 위해서는 난방설계용 외기조건, 즉 표준기상 데이터가 필요하다. 그러나, 현재 국내에는 건물의 냉난방 설계를 위한 표준기상 자료가 대도시 지역의 일부에 대하여만 발표되어 있다. 이것은 농업시설에 대해서는 적용이 불가능하므로 농업 시설 설계를 위한 개략적인 표준기상 데이터의 선정이 요망된다. (중략)

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.204-211
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• 2019

The purpose of this study is to provide basic data for setting environmental design standards for domestic greenhouses. We conducted experiments on thermal environment measurement at two commercial greenhouses where hot water heating system is adopted. We analyzed heat transfer characteristics of hot water heating pipes and heat emission per unit length of heating pipes was presented. The average air temperature in two greenhouses was controlled to $16.3^{\circ}C$ and $14.6^{\circ}C$ during the experiment, respectively. The average water temperature in heating pipes was $52.3^{\circ}C$ and $45.0^{\circ}C$, respectively. Experimental results showed that natural convection heat transfer coefficient of heating pipe surface was in the range of $5.71{\sim}7.49W/m^2^{\circ}C$. When the flow rate in heating pipe was 0.5m/s or more, temperature difference between hot water and pipe surface was not large. Based on this, overall heat transfer coefficient of heating pipe was derived as form of laminar natural convection heat transfer coefficient in the horizontal cylinder. By modifying the equation of overall heat transfer coefficient, a formula for calculating the heat emission per unit length of hot water heating pipe was developed, which uses pipe size and temperature difference between hot water and indoor air as input variables. The results of this study were compared with domestic and foreign data, and it was found to be closest to JGHA data. The data of NAAS, BALLS and ASHRAE were judged to be too large. Therefore, in order to set up environmental design standards for domestic greenhouses, it is necessary to fully examine those data through further experiments.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.215-224
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• 2009

A survey on the actual state of heating, cooling, ventilation, and air-flow and experimental measurement of temperature and humidity distribution in tomato greenhouse were performed to provide fundamental data required in the development of air-flow control technology. In single-span plastic houses, which account for most of 136 tomato greenhouses surveyed, roof windows, ventilation and air-flow fans were installed in a low rate, and installation specs of those facilities showed a very large deviation. There were no farms installed greenhouse cooling facilities. In the hot air heating system, which account for most of heating type, installation specs of hot air duct showed also a large deviation. The exhaust air temperature and wind speed in hot air duct also were measured to have a big difference depending on the distance from the heater. We are using the maximum difference as indicator to determine whether temperature distribution is uniform. However if the temperature slope is not identical in greenhouse, it can't represent the uniformity. We analyzed relation between the maximum difference and the uniformity of temperature and humidity distribution. The uniformity was calculated using the mean and standard deviation of data from 12 measuring points. They showed high correlation but were represented differently by linear in the daytime and quadratic in the nighttime. It could see that the uniformity of temperature and humidity distribution was much different according to greenhouse type and heating method. The installation guidelines for ventilation and air-flow fan, the spread of greenhouse cooling technology for year-round stable production, and improvement of air duct and heating system, etc. are needed.