Uniformity Analysis of Microclimate in Vertical Farm Using Computational Fluid Dynamics

Kyoung-min Kim; Hyo-hyeog Jeong; In-bok Lee

doi:10.12791/KSBEC.2026.35.3.262

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2026 Vol.35, Issue 3 Preview Page Next Page

Original Articles

Uniformity Analysis of Microclimate in Vertical Farm Using Computational Fluid Dynamics 전산유체역학을 이용한 수직농장 내부 미기상 환경의 균일도 분석

31 July 2026. pp. 262-273

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Abstract

As urbanization reduces farmland and climate change destabilizes agricultural supply chains, controlled-environment vertical farming has drawn attention for its high productivity per unit area, reduced water use, and stable year-round production. Because such facilities are enclosed and rely on artificial lighting and mechanical climate control, non-uniform air temperature and airflow readily cause thermal stratification and stagnation, and uneven growth within a batch can delay harvest and cause economic loss. This study used Computational Fluid Dynamics (CFD) to compare the uniformity of the internal microclimate of a vertical farm according to inlet–outlet position. A full-scale model of a multi-tier cultivation room (6.8m × 11.0m × 3.2m) growing lettuce (Lactuca sativa L.) was developed, with the canopy represented as a porous medium coupled with sensible- and latent-heat exchange. Sixteen cases combining the height and the wall or ceiling placement of the inlet and outlet were simulated under an identical ventilation rate of 56.2 air changes per hour, and performance was compared using temperature and velocity distributions and the coefficient of variation (CV). Inlet-outlet position decisively affected thermal and airflow uniformity. Case A-1, with both openings on the same short wall and the inlet below the outlet, gave the most uniform thermal environment (temperature CV 0.08%) and the fewest stagnant regions (velocity CV 6.35%), because the incoming air circulated through the whole cultivation space before discharge and thereby offset buoyancy-driven stratification. In contrast, a lower inlet paired with an outlet on the opposite wall or the ceiling caused short-circuit airflow, raising the temperature CV to 0.26% and leaving a hot stagnant region in the upper space (Case C-4). An inlet on the long side walls also lowered uniformity because the air did not reach the far end. Optimizing inlet-outlet position is therefore essential in designing vertical-farm ventilation systems.

Keywords

air changes per hour

buoyancy

coefficient of variation

lettuce

porous medium

본 연구는 CFD를 활용하여 입·배기구 위치에 따른 수직농장 내부환경의 균일성 비교를 목적으로 수행되었다. 대상 시설은 다층 구조의 수직농장으로 설정되었으며, 작물군을 다공성 매질로 모델링하고 현열 및 잠열 교환을 포함하여 실제 재배 환경을 반영하였다. 입기구와 배기구의 높이 및 벽면·천장 배치를 조합하여 총 16개의 Case를 구성하고, 온도 분포, 유속 분포 및 CV를 기반으로 성능을 비교하였다. 분석 결과, 입·배기구의 상대적 위치는 시설 내부의 열·기류 균일성에 결정적인 영향을 미치는 것으로 나타났다. 좁은 면의 벽(Wall1)의 동일한 벽면에 입기구와 배기구를 배치하고 입기구를 배기구보다 낮게 둔 Case A-1이 온도 CV 0.08%로 가장 균일한 열환경을 형성하였으며, 유속 CV 또한 6.35%로 가장 낮아 정체 영역이 가장 적었다. 이는 유입 공기가 재배 공간 전반을 순환한 뒤 배출되어 부력에 의한 수직 온도 성층화를 효과적으로 상쇄하였기 때문이다. 반면 입기구를 하부에 두고 배기구를 천장에 배치한 Case C-4에서는 유입 공기가 상부 고온 영역과 혼합되지 못한 채 배기구로 직접 빠져나가는 현상이 발생하여, 온도 CV가 0.26%로 가장 높고 상부에 고온 정체 영역이 형성되었다. 또한 넓은 측벽(Wall 2, 4)에 입기구를 배치한 경우 유입 공기가 길이 방향 후단부까지 충분히 도달하지 못해 균일도가 상대적으로 저하되었다. 최종적으로 좁은 면의 벽과 동일 벽면에서 입기구를 배기구보다 낮게 배치하는 구조가 온도와 유속 균일성을 동시에 확보하는 입·배기구 조건이었다. 본 연구 결과는 수직농장의 환기 시스템 설계 시 입·배기구 위치 최적화의 중요성을 제시하며, 향후 에너지 효율 향상 및 작물 생산성 증대에 기여할 수 있는 기초 자료로 활용될 수 있다. 다만 본 연구는 실측 검증 없이 검증된 선행 연구의 물리 모델과 경계 조건을 채택하였으므로, 절대적인 온도·유속 값보다는 입·배기구 위치에 따른 상대적 균일성 경향의 비교에 그 의의가 있다. 또한 단일 재배실 형상과 고정 환기율(56.2 ACH) 조건에 한정되며, 기공 저항을 노지에 대한 상수로 두어 수직농장 내부에서의 생육 단계별 증산 변화를 반영하지 못한 한계가 있다. 따라서 향후에는 실측 기반의 정량적 검증, 다양한 규모·환기량 조건으로의 확장, 순환팬을 통한 재배단 간 기류 혼합 등 미기상 균일성 향상 방안에 대한 후속 연구가 필요하다.

키워드

공기교체율

다공성 매질

변동계수

부력

상추

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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 : 35
No :3
Pages :262-273
Received Date : 2026-07-10
Revised Date : 2026-07-28
Accepted Date : 2026-07-28
DOI :https://doi.org/10.12791/KSBEC.2026.35.3.262

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

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