Thermal Performance of Rear Air Cavities in BAPV Applications Compared with Korean Design Standards

Tae-Gyeom An; Ji-Hye Park; Young Tae Chae

doi:10.21086/ksles.2026.2.33.1.062

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2026 Vol.33, Issue 1 Preview Page

Research Article

Thermal Performance of Rear Air Cavities in BAPV Applications Compared with Korean Design Standards 건물 외피 부착형 태양광 (BAPV) 후면 중공층의 열적 거동과 국내 설계기준과의 비교분석

28 February 2026. pp. 62-69

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Abstract

This study examines the validity of the constant thermal resistance applied to enclosed air cavities thicker than 10 mm in the Korean Energy Saving Design Standard for PV-backed building envelopes. Thermal–fluid simulations were performed using ANSYS CFX with various combinations of turbulence and radiation models. The Generalized k–ω and Discrete Transfer model combination showed the most stable convergence and was selected for analysis. Cavity thicknesses from 10 to 100 mm were investigated to evaluate thermal resistance and airflow characteristics. The results indicate conduction-dominated heat transfer below 20 mm, laminar natural convection at 30 mm, and turbulent natural convection above 40 mm. Although the thermal resistance increase converges in the turbulent regime, it does not become constant. At 100 mm thickness, the thermal resistance increased by about 52% compared with the fixed standard value, suggesting the need for a complementary evaluation approach to better reflect the thermal behavior of thick PV air cavities.

Keywords

Building-Applied Photovoltaic (BAPV)

Air Cavity

Thermal Performance

CFD

Korean Energy Saving Design Standard

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Information

Publisher :The Korean Society of Living Environmental System
Publisher(Ko) :한국생활환경학회
Journal Title :Journal of The Korean Society of Living Environmental System
Journal Title(Ko) :한국생활환경학회
Volume : 33
No :1
Pages :62-69
Received Date : 2026-02-21
Revised Date : 2026-02-26
Accepted Date : 2026-02-27
DOI :https://doi.org/10.21086/ksles.2026.2.33.1.062

Journal of The Korean Society of Living Environmental System ISSN:1226-1289(Print) 한국생활환경학회

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