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2015 Vol.24, Issue 2
Experimental Study on the Infiltration Loss in Plastic Greenhouses Equipped with Thermal Curtains

보온커튼을 설치한 플라스틱 온실의 틈새환기전열량 실측조사

Sang-Woon Nam1*
,
Hyun-Ho Shin1
남 상운1*
,
신 현호1
1Department of Agricultural and Rural Engineering, Chungnam National University, Daejeon 305-764, Korea
1충남대학교 지역환경토목학과
*Corresponding author: swnam@cnu.ac.kr
30 April 2015. pp. 100-105
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Abstract

The calculation method of infiltration loss in greenhouse has different ideas in each design standard, so there is a big difference in each method according to the size of greenhouses, it is necessary to establish a more accurate method that can be applied to the domestic. In order to provide basic data for the formulation of the calculation method of greenhouse heating load, we measured the infiltration rates using the tracer gas method in plastic greenhouses equipped with various thermal curtains. And then the calculation methods of infiltration loss in greenhouses were reviewed. Infiltration rates of the multi-span and single-span greenhouses were measured in the range of 0.042~0.245h-1 and 0.056~0.336h-1 respectively, single-span greenhouses appeared to be slightly larger. Infiltration rate of the greenhouse has been shown to significantly decrease depending on the number of thermal curtain layers without separation of single-span and multi-span. As the temperature differences between indoor and outdoor increase, the infiltration rates tended to increase. In the range of low wind speed during the experiments, changes of infiltration rate according to the outdoor wind speed could not find a consistent trend. Infiltration rates for the greenhouse heating design need to present the values at the appropriate temperature difference between indoor and outdoor. The change in the infiltration rate according to the wind speed does not need to be considered because the maximum heating load is calculated at a low wind speed range. However the correction factors to increase slightly the maximum heating load including the overall heat transfer coefficient should be applied at the strong wind regions. After reviewing the calculation method of infiltration loss, a method of using the infiltration heat transfer coefficient and the greenhouse covering area was found to have a problem, a method of using the infiltration rate and the greenhouse volume was determined to be reasonable.

Keywords
energy saving
environmental design
heating load
infiltration rate
tracer gas method

온실의 난방부하 중 틈새환기전열부하 산정방법은 설 계 기준마다 제각각이고, 온실의 규모에 따라 각각의 방 법에는 큰 차이가 있으므로 보다 정확히 국내에 적용할 수 있는 방법을 정립할 필요가 있다. 본 연구에서는 원 예시설의 환경설계 중 난방부하 산정방법 정립에 필요한 기초자료를 제공할 목적으로 다양한 종류의 보온커튼을 설치한 단동 및 연동 플라스틱 온실에서 추적가스법을 이용하여 틈새환기율을 실측하였으며, 온실의 틈새환기 전열부하 산정방법을 검토하였다. 연동온실의 틈새환기 율은 0.042~0.245h-1의 범위로 측정되었으며 단동온실의 틈새환기율은 0.056~0.336h-1의 범위로 측정되어 단동온 실이 약간 큰 것으로 나타났다. 온실의 틈새환기율은 단 동, 연동 구분없이 보온커튼의 층수에 따라 크게 감소하 는 것으로 나타났다. 또한 틈새환기율은 온실의 실내외 기온차가 커질수록 증가하는 경향을 보였으나, 실험기간 동안의 낮은 풍속 범위에서 외부 풍속에 따른 틈새환기 율의 변화는 일정한 경향을 찾을 수 없었다. 온실의 난 방설계를 위한 틈새환기율은 적정 실내외 기온차에서의 값을 제시할 필요가 있고, 최대난방부하 산정의 기준이 되는 낮은 풍속 범위에서 풍속에 따른 틈새환기율의 변 화는 고려하지 않아도 되는 것으로 고찰되었다. 다만 강 풍지역에서는 열관류율을 포함하여 최대난방부하를 약간 증가시키는 보정계수의 적용이 필요할 것으로 판단되었 다. 온실의 틈새환기전열부하 산정방법을 검토한 결과 틈새환기전열계수와 온실의 피복면적을 이용하는 방법은 문제가 있는 것으로 나타났으며, 틈새환기율과 온실의 체적을 이용하는 방법이 합리적인 것으로 판단되었다.

키워드
난방부하
에너지절감
추적가스법
틈새환 기율
환경설계
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Information
  • Publisher :The Korean Society for Bio-Environment Control
  • Publisher(Ko) :(사)한국생물환경조절학회
  • Journal Title :Protected Horticulture and Plant Factory
  • Journal Title(Ko) :시설원예ㆍ식물공장
  • Volume : 24
  • No :2
  • Pages :100-105
  • Received Date : 2015-04-16
  • Revised Date : 2015-05-11
  • Accepted Date : 2015-05-20
  • DOI :https://doi.org/10.12791/KSBEC.2015.24.2.100
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