DOI QR코드

DOI QR Code

Evaluation of Natural Ventilation Performance for Multi-span Plastic Greenhouses

다연동 플라스틱 온실의 자연환기성능 평가

  • Nam, Sang-Woon (Department of Agricultural and Rural Engineering, Chungnam National University) ;
  • Kim, Young-Shik (Deptartment of Plant and Food Sciences, Sangmyung University) ;
  • Seo, Dong-Uk (Department of Agricultural and Rural Engineering, Chungnam National University)
  • 남상운 (충남대학교 지역환경토목학과) ;
  • 김영식 (상명대학교 식물식품공학과) ;
  • 서동욱 (충남대학교 지역환경토목학과)
  • Received : 2013.01.04
  • Accepted : 2013.01.25
  • Published : 2013.03.31

Abstract

Environmental measurements in the many different types of horticultural farms were carried out to evaluate the ventilation performance for multi-span plastic greenhouses according to the eaves height, the number of spans, the existence of side wall vents and the position of roof vents. Hydroponic tomatoes were being cultivated in all experimental greenhouses, and ventilation rates of the greenhouses were analyzed by the heat balance method. It showed that the ventilation rate in the greenhouse with 4 m eaves height increased about 22% compared to the greenhouse with 2 m eaves height. The ventilation rate in the greenhouse with 9 spans decreased about 17% compared to the greenhouse with 5 spans. In the greenhouse with 9 spans, if there were no side wall vents, the ventilation rate showed about a third of the case that side wall vents were open. Overall, as the eaves height was higher and the number of spans was smaller in multi-span greenhouses, the natural ventilation performance was better. And the ventilation performance was best in the greenhouse which the eaves height was high and the position of roof vents was ridge, not gutter. Therefore, in order to maximize the natural ventilation performance, multi-span plastic greenhouses need to improve their structures such as that make the eaves height higher, place the roof vents on the ridge, install the side wall vents as much as possible, and the number of spans is limited to about 10 spans.

측고, 연동수, 측창의 유무 및 천창의 위치에 따른 다연동 온실의 환기성능을 평가하기 위하여 다양한 유형의 연동 플라스틱 온실을 대상으로 실제 농가의 재배현장에서 환경계측 실험을 수행하였다. 실험 대상 온실은 모두 토마토를 수경재배하고 있는 농가였으며, 열수지 방법으로 환기율을 비교 분석하였다. 측고가 4m인 온실은 측고가 2m인 온실에 비하여 22% 정도의 환기율이 증가하는 것으로 나타났다. 9연동 온실은 5연동 온실에 비하여 17% 정도의 환기율이 감소하는 것으로 나타났다. 9연동 온실에서 측창이 없는 경우에는 측창을 설치한 경우 보다 환기율이 1/3 정도로 낮게 나타났다. 전체적으로 다연동 온실의 환기성능은 측고가 높을수록 좋고, 연동수가 많을수록 떨어지며, 측창이 없으면 현저하게 저하하는 것으로 나타났다. 또한, 측고가 높고 천창을 용마루에 설치한 경우의 환기성능이 가장 우수한 것으로 나타났다. 따라서 다연동 온실의 자연환기 성능을 극대화하기 위해서는 온실의 측고는 높이고, 지붕 환기창의 위치는 곡부가 아니라 용마루에 설치하며, 측창을 반드시 설치하고, 연동수는 10연동 내외로 제한하는 등의 구조개선이 필요하다.

Keywords

References

  1. ASAE. 2003. Standards. Heating, ventilating and cooling greenhouses. ASAE. St. Joseph, Michigan. p. 663-670.
  2. BioIn. 2012. Biotechnology trend. Industry No. 465 2000-08-05. Biotech Information Portal (http://www.bioin.or.kr).
  3. Byeon, D.H. 2010. Evaluation of greenhouse functionality according to the change of eaves height. Thesis for the degree of Master. Kyungpook National University (in Korean).
  4. Fernandez, J.E. and B.J. Baily. 1992. Measurement and prediction of greenhouse ventilation rates. Agricultural and Forest Meteorology 58:229-245. https://doi.org/10.1016/0168-1923(92)90063-A
  5. Hellickson, M.A. and J.N. Walker. 1983. Ventilation of agricultural structures. ASAE. St. Joseph, Michigan. p. 103-124, p. 297-319.
  6. Kim, M.K., K.S. Kim, and H.J. Kwon. 2001. The cooling effect of fog cooling system as affected by air exchange rate in natural ventilation greenhouse. Journal of Bio-Environment Control 10(1):10-14 (in Korean).
  7. Kim, M.K., S.W. Nam, W.M. Seo, Y.C. Yoon, S.G. Lee, and H.W. Lee. 2000. Agricultural strutures engineering. Hyangmoonsa Press. p. 175-183 (in Korean).
  8. Lee, G.M., K.S. Park, Y.I. Kim, and T.H Kim. 1995a. Development of roll-up ventilation system for pipe-constructed plastic film greenhouse. J. Bio. Fac. Env. 4(2):232-239 (in Korean).
  9. Lee, S.Y., H.H. Kim, H. Chun, Y.S. Kwon, and G.M. Lee. 1995b. Improvement of coverings and ventilation methods in 1-2W type vinyl house and growth responses of tomatoes. Proceeding of Bio. Fac. Env. 4(2):97-99 (in Korean).
  10. Li, S. and D.H. Willits. 2008. Comparing low-pressure and high-pressure fogging systems in naturally ventilated greenhouses. Biosystems Engineering 101:69-77. https://doi.org/10.1016/j.biosystemseng.2008.06.004
  11. Lindley, J.A. and J.H. Whitaker. 1996. Agricultural buildings and structures. ASAE. St. Joseph, Michigan. p. 463-484.
  12. Nam, S.W. 2000a. Actual utilization and thermal environment of greenhouses according to several cooling methods during summer season. Journal of Bio-Environment Control 9(1):1-10 (in Korean).
  13. Nam, S.W. 2000b. Application of heat balance model to design of ventilating and cooling greenhouses. Journal of Bio-Environment Control 9(4):201-206 (in Korean).
  14. Nam, S.W. and Y.S. Kim. 2009. Actual state of structures and environmental control facilities for tomato greenhouses in Chungnam region. Jour. Agri. Sci. 36(1):73-85 (in Korean).
  15. Nam, S.W., Y.S. Kim, and A.J. Both. 2011. Analysis on the ventilation performance of single-span tomato greenhouse with roof windows. Journal of Bio-Environment Control 20(2):78-82 (in Korean).
  16. Tachibana, K., K. Hanekura, K. Takahashi, and E. Ohtsuka. 1979. Design and construction of greenhouses for protected horticulture. Ohm Pub. Tokyo. p. 91-103 (in Japanese).
  17. Willits, D.H., C.A. Yunker, and S. Li. 2006. Air exchange rates in a naturally ventilated greenhouse using different vent configurations. Paper No. 06-4095. ASABE. St. Joseph, Michigan.
  18. Yu, I.H., E.H. Lee, M.W. Cho, H.R. Ryu, and Y.C. Kim. 2012. Development of multi-span plastic greenhouse for tomato cultivation. Journal of Bio-Environment Control 21(4):428-436 (in Korean). https://doi.org/10.12791/KSBEC.2012.21.4.428