Evaluation of Air Diffusion Performance and Thermal Environment by Additional Vanes of Ceiling-mounted Air Conditioner

Kyu-Nam Rhee

doi:10.7836/kses.2025.45.4.031

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2025 Vol.45, Issue 4 Preview Page Next Page

Research Article

Evaluation of Air Diffusion Performance and Thermal Environment by Additional Vanes of Ceiling-mounted Air Conditioner 천장형 에어컨의 베인 추가 설치에 의한 실내 기류 확산성능 및 열환경 평가

30 August 2025. pp. 31-42

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Abstract

Ceiling-mounted air conditioners often cause thermal discomfort when the discharged cold air descends directly to the occupied zone, generating a cold draught for occupants. To prevent the local discomfort, guide vanes are commonly installed to deflect the air flow from the ceiling-mounted air conditioner; however, the effect of additional vanes on the air diffusion performance and thermal environment has not been investigated in previous studies. In this study, a length-adjustable vane was developed to adjust the air flow passing through the vane. The impacts of the vane on the air diffusion performance and thermal environment were evaluated in a university lecture room located in the Busan region. The field test results showed that the vane was effective in reducing the air velocity and elevating the air temperature in the occupied zone, whereas the stretched vane was ineffective in mitigating the air velocity in the zone. The air diffusion performance index (ADPI) was not degraded by applying additional vanes. The application of the vanes resulted in the slight enhancement of ADPI from 79.6% to 80.4%, satisfying the ASHRAE standard for room air diffusion. In addition, the vanes were effective in achieving thermal comfort near the neutral state. The predicted mean vote (PMV) of the occupied zone met the thermal comfort category A or B of the ISO 7730 standard. The developed vanes effectively improved the air temperature and velocity distribution, ADPI, and PMV. Further study is suggested to investigate the impact of additional vanes under various cooling loads and operating conditions (e.g., supply air flow rate, temperature) of air conditioners.

Keywords

Ceiling-mounted air conditioner

Air velocity

Temperature distribution

Air diffusion

PMV

Field test

키워드

천장형 에어컨

기류 속도

온도분포

기류 확산

예상평균 온열감

현장 실험

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Information

Publisher :Korean Solar Energy Society
Publisher(Ko) :한국태양에너지학회
Journal Title :Journal of the Korean Solar Energy Society
Journal Title(Ko) :한국태양에너지학회 논문집
Volume : 45
No :4
Pages :31-42
Received Date : 2025-07-13
Revised Date : 2025-07-28
Accepted Date : 2025-07-29
DOI :https://doi.org/10.7836/kses.2025.45.4.031

Journal of the Korean Solar Energy Society ISSN:1598-6411(Print) 2508-3562(Online) 한국태양에너지학회 논문집

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