• Title, Summary, Keyword: greenhouse

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A Study on the Thermal Environment in the Multipurpose Greenhouse in Winter (다목적 그린하우스의 동절기 실내온열환경 특성에 관한 실측 연구)

  • Kim, Soon-Joo;Na, Su-Yeun
    • Journal of the Korean Solar Energy Society
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    • v.27 no.3
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    • pp.15-21
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    • 2007
  • The purpose of this study is to provide the basic data for passive control and energy conservation strategies of multipurpose greenhouse. Passive design strategies which are appropriate to Jeju environmental circumstance were applied in the multipurpose greenhouse. The field measurement were conducted to examine relationship of micro climate and indoor thermal environment in the multipurpose greenhouse. The result of this study can be summarized as follow ; (1) The indoor temperature was ranged from 5 to $21^{\circ}C$ without a heating system, when the exterior temperature was -1 to $19^{\circ}C$. (2) The multi-purpose greenhouse requires almost no heating energy in winter, when it is used as a greenhouse, an exhibition hall or a cafeteria.

Analysis of Potential Reductions of Greenhouse Gas Emissions on the College Campus through the Energy Saving Action Programs

  • Woo, Jeongho;Choi, Kyoung-Sik
    • Environmental Engineering Research
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    • v.18 no.3
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    • pp.191-197
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    • 2013
  • Republic of Korea announced the reduction target to be around 30% of business as usual greenhouse gas emissions by 2020. College campuses were ranked at the 5th of high energy consumption areas in the building sectors. Target management scheme was designed to set greenhouse gas emissions target including several college campuses. Previous studies showed the amount of greenhouse gas emissions with several assumptions such as the applications of renewable energy systems and light emitting diode lamps, etc. Long-range Energy Alternatives Planning model was utilized to simulate future greenhouse gas emissions. This study sets standard model labs for energy saving action programs by applying guidance studies. It has been deduced that energy saving action programs was responsible for reducing 949.5 kWh for each standard model lab and the total reduction of all 59 model labs in the Engineering College building has been calculated to 56,020.5 kWh. The objective of the study is to provide guidelines on standard model laboratory for greenhouse gas emissions reduction on the campus.

Control of Automated Greenhouse Based on a PC (PC 기반 자동화 시설 하우스 제어)

  • 김기환
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.9
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    • pp.644-649
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    • 2004
  • To control a greenhouse is to control environmental parameters in greenhouse. Controlled environments may be as simple as saran-covered shade houses or as complex as growth chambers. Although greenhouses are probably the most common example of a controlled environment used in agricultural/horticultural production, the type of controlled environment or system that is needed depends upon the climate, time of year, crops being produced and the environmental parameters that must be controlled. In this contribution puts emphasis on construction of automatic-controlled greenhouse system by personal computer.

Development of Fog Cooling Control System and Cooling Effect in Greenhouse (온실 포그 냉방 제어시스템 개발 및 냉방효과)

  • Park, Seok Ho;Moon, Jong Pil;Kim, Jin Koo;Kim, Seoung Hee
    • Protected Horticulture and Plant Factory
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    • v.29 no.3
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    • pp.265-276
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    • 2020
  • This study was conducted to provide a basis for raising farm income by increasing the yield and extending the cultivation period by creating an environment where crops can be cultivated normally during high temperatures in summer. The maximum cooling load of the multi-span greenhouse with a floor area of 504 ㎡ was found to be 462,609 W, and keeping the greenhouse under 32℃ without shading the greenhouse at a high temperature, it was necessary to fog spray 471.6 L of water per hour. The automatic fog cooling control device was developed to effectively control the fog device, the flow fan, and the light blocking device constituting the fog cooling system. The fog cooling system showed that the temperature of the greenhouse could be lowered by 6℃ than the outside temperature. The relative humidity of the fog-cooled greenhouse was 40-80% during the day, about 20% higher than that of the control greenhouse, and this increase in relative humidity contributed to the growth of cucumbers. The relative humidity of the fog cooling greenhouse during the day was 40-80%, which was about 20% higher than that of the control greenhouse, and this increase in relative humidity contributed to the growth of cucumbers. The yield of cucumbers in the fog-cooled greenhouse was 1.8 times higher in the single-span greenhouse and two times higher in the multi-span greenhouse compared to the control greenhouse.

An Analysis of 10th Grade Science Textbook as an Origin of Misconception on Greenhouse Effect Concept (온실효과 개념에 대한 오개념 원인으로서의 10학년 과학 교과서 분석)

  • Kook, Dong-Sik
    • Journal of The Korean Association For Science Education
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    • v.23 no.5
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    • pp.592-598
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    • 2003
  • The purpose of this study is to analyze the tenth grade science textbooks as an origin of misconception on greenhouse effect concept and find incorrect descriptions on that concept and then suggest some improved schemes. Some incorrect descriptions, pictures. tables and experiments related to misconceptions on greenhouse effect were found in textbooks. They are considered to contribute to form and reinforce misconceptions on that concept : the most important gas of greenhouse effect, the role of $CO_2$ on the change of greenhouse effect. global warming. energy sources, greenhouse experiments and the physical processes of greenhouse effect. So some improved schemes were suggested

A Study on the Greenhouse Water Curtain System: Heat Transfer Characteristics

  • 손원명;한길영
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.32 no.E
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    • pp.80-87
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    • 1990
  • Energy balance equations Were developed to describe the heat transfer mechanisms in a double layer plastic greenhouse with a water curtain system. Heat transfer variables were determined by using various temperature data measured in a conventional prototype semicircular cross-section greenhouse over a range of water temperatures and water flow rates. The heat transfer coefficient between flowing water and greenhouse air was independent of water flow rates. But the heat transfer coefficient between water surface and the stagnant air space within the double plastic layer was dependent on water flow rates. Substituting the heat transfer coefficients, determined from the energy balance equations in the heat transfer equations, demonstrated various relationships among ambient air temperature, greenhouse air temperature, water temperature, and water flow rates. The heating benefits were linearly related to not only the inside and outside air temperatures but also to the water temperature. The energy conservation effects of the water curtain system were found even initial water temperatures were considerably lower than the greenhouse setting temperatures. Sensitivity analysis for heat transfer coefficients demonstrated that the heat transfer coefficient between greenhouse air and the stagnant air within the plastic layers was the most significant coefficient in the estimation of heating effects.

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Growth Characteristics of Cherry Tomato in Greenhouse using Far Infrared Heating Systems (원적외선 난방시스템이 방울토마토 생육에 미치는 영향)

  • Kim, H.J.;Li, H.;Kang, T.H.;Ning, X.F.;Han, C.S.;Cho, S.C.
    • Journal of Biosystems Engineering
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    • v.34 no.3
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    • pp.161-166
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    • 2009
  • This study was conducted to investigate the growth characteristics of cherry tomatoes in greenhouse using far infrared heating system. The far infrared greenhouse heating systems were installed in two ways on the greenhouse side wall and at the greenhouse ceiling. The heating characteristics of far infrared heating system were analyzed by investigating the heating load, internal temperature, energy consumption, growth characteristics and quality evaluation. The results were compared with heated air heating system using kerosene. The results showed that tomatoes grown in the greenhouse with the far infrared heating system had relatively better plant height, leaf length, leaf width, stem diameter than ones from the greenhouse with hot air heating system and both heating methods had no significant difference on Cherry tomato sugar contents. At the same time, the far infrared heating system reduced heating cost from 34.5 to 41.4% on comparing with hot air heating system.

Economic Analysis of Cooling-Heating System Using Ground Source Heat in Horticultural Greenhouse (시설원예의 지열냉·난방시스템 경제성 분석)

  • Ryoo, Yeon-Su;Joo, Hye-Jin;Kim, Jin-Wook;Park, Mi-Lan
    • Journal of the Korean Solar Energy Society
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    • v.32 no.6
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    • pp.60-67
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    • 2012
  • Government Geothermal Cooling-Heating Projects has made efforts to reduce GHG(Greenhouse Gas) emissions and to manage cost of greenhouse farm households. This study evaluated the economic benefits of heating load rate of change by comparing Geothermal Cooling-Heating System with the existing system(greenhouse diesel heating) in the Government Geothermal Cooling-Heating Projects. Economic analysis results shows that, 1) When installing the Cooling-Heating system according to the ratio of 70% heating load in policy standards, the geothermal cooling-heating system has economic efficiency with greenhouse type or scale independent because the investment cost is recovered within 7 years. And It was more economic efficiency the ratio of 50% heating load than70% heating load. 2) When installing the Cooling-Heating system according to the glass greenhouse of the ratio of 90% heating load, pay period of investment cost is recovered within 5 years. Therefore it is necessary to apply flexible heating sharing according to greenhouse type or scale.

Greenhouse Cooling by Fog System (FOG SYSTEM 을 이용한 여름철 온실냉방)

  • 서원명
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.41 no.1
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    • pp.60-71
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    • 1999
  • This study was performed to improve underirable warm greenhouse environment by fog cooling system in summer season. The resultsof droplet size analysis and cooling effects for fog cooling system are summarized as follows ; 1. At the pump pressure of 70kgf/$\textrm{cm}^2$ , the mean (SMD) drop size was 22.6${\mu}{\textrm}{m}$ and the maximum and minimum drop size was 45.68${\mu}{\textrm}{m}$ and 1.73${\mu}{\textrm}{m}$ , respectively, and almost all of the drop size was less than 40${\mu}{\textrm}{m}$. 2. The temperature of fog cooling greenhouse with 60% shading was dropped more than 2$^{\circ}C$ below the ambient temperature , while the greenhouse temperature without shading was 1$^{\circ}C$ higher than the ambient temperature. 3. It was found that fog spraying intervals were significantly influential on cooling effect. 4. When the greenhouse was ventilated sufficiently by natural vent system, green house temperature could be maintained by 2.5$^{\circ}C$ lower than the ambient temperature, while it was difficult to drop the greenhouse temperature below ambient temeperature without sufficient ventilation. 5. It was found that the temperature of experimental greenhouse could be maintained 3$^{\circ}C$ to 14$^{\circ}C$ lower that of control greenhouse though there were variations depending on experimental and weather conditions.

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