Environmental Prediction in Greenhouse According to Modified Greenhouse Structure and Heat Exchanger Location for Efficient Thermal Energy Management

In Seon Jeong; Chung Geon Lee; La Hoon Cho; Sun Yong Park; Seok Jun Kim; Dae Hyun Kim; Jae-Heun Oh

doi:10.12791/KSBEC.2021.30.4.278

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2021 Vol.30, Issue 4 Preview Page Next Page

Original Articles

Environmental Prediction in Greenhouse According to Modified Greenhouse Structure and Heat Exchanger Location for Efficient Thermal Energy Management 효율적인 열에너지 관리를 위한 온실 형상 및 열 교환 장치 위치 개선에 따른 온실 내부 환경 예측

31 October 2021. pp. 278-286

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Abstract

In this study, based on the Computational Fluid Dynamics (CFD) simulation model developed through previous study, inner environmenct of the modified glass greenhouse was predicted. Also, suggested the optimal shape of the greenhouse and location of the heat exchangers for heat energy management of the greenhouse using the developed model. For efficient heating energy management, the glass greenhouse was modified by changing the cross-section design and the location of the heat exchanger. The optimal cross-section design was selected based on the cross-section design standard of Republic of Korea's glass greenhouse, and the Fan Coil Unit(FCU) and the radiating pipe were re-positioned based on “Standard of greenhouse environment design” to enhance energy saving efficiency. The simulation analysis was performed to predict the inner temperature distribution and heat transfer with the modified greenhouse structure using the developed inner environment prediction model. As a result of simulation, the mean temperature and uniformity of the modified greenhouse were 0.65°C, 0.75%p higher than those of the control greenhouse, respectively. Also, the maximum deviation decreased by an average of 0.25°C. And the mean age of air was 18 sec. lower than that of the control greenhouse. It was confirmed that efficient heating energy management was possible in the modified greenhouse, when considered the temperature uniformity and the ventilation performance.

Keywords

computational fluid dynamics

cross-section design

heat exchanger

mean age of air

microclimate

본 연구에서는 단면설계 및 열 교환 장치 위치 변경을 통해 온실의 구조 변경을 진행하였으며, 선행연구를 통해 개발된 모델을 근간으로 하여 개선 여부에 따른 온실 내부 환경을 예측하였다. 단면형상과 열 교환 장치의 개선 후 유속 변화에 따른 시뮬레이션 분석을 진행하였으며, 이 때 온도와 균일도는 각각 평균 0.65°C, 0.75%p 상승함을 확인하였다. 해석대상 온실과 같은 소규모 온실의 경우 방열관의 난방성능 개선보다 FCU에 의해 형성되는 공기 유동이 균일한 환경 조성에 더 큰 영향을 미치는 것으로 판단된다. 개선 전 ‧ 후 온실에 환기시스템 적용 시 공기 유동 특성 분석을 위해 시뮬레이션 분석을 진행하였다. 공기 유동과 공기령은 유사한 분포를 보였으며, 개선 후 온실의 공기령이 개선 전 온실 대비 18초 낮게 나타났다. 개선 전 ‧ 후 온실 시뮬레이션 분석 결과 전체적으로 개선된 온실에서의 평균온도 및 온도 균일도 상승, 최대편차 감소 등 내부 환경의 균일성이 향상됨을 확인하였다. 선행연구로 개발된 모델은 형상 변경, 열 교환 장치 위치 변경 등에 따라 변화하는 온실 내부 환경을 예측할 수 있음을 확인하였으며, 온실 설계, 온실 내 난방시스템 설계 등의 분야에 적용 가능할 것으로 판단된다.

키워드

열 교환 장치

단면설계

전산유체역학

미기상

공기령

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Information

Publisher :The Korean Society for Bio-Environment Control
Publisher(Ko) :(사)한국생물환경조절학회
Journal Title :Journal of Bio-Environment Control
Journal Title(Ko) :생물환경조절학회지
Volume : 30
No :4
Pages :278-286
Received Date : 2021-03-31
Revised Date : 2021-09-23
Accepted Date : 2021-09-27
DOI :https://doi.org/10.12791/KSBEC.2021.30.4.278

Journal of Bio-Environment Control ISSN:1229-4675(Print) 2765-3641(Online) 생물환경조절학회지

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