Performance Evaluation of Temperature Distribution Uniformity in AHU Duct Using Static Airmixer

Junwoo Lee; Hanung Jeong; minjae Jeong; Kyungmo Kang

doi:10.7836/kses.2026.46.3.223

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2026 Vol.46, Issue 3 Preview Page Next Page

Performance Evaluation of Temperature Distribution Uniformity in AHU Duct Using Static Airmixer 정적 공기 혼합장치를 이용한 AHU 덕트 내 온도 분포 균일화 성능 평가

30 June 2026. pp. 223-235

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Abstract

Energy efficiency in HVAC systems has become increasingly significant given the growing demand for carbon reduction. In air-handling units (AHU), the complete mixing of Return Air (RA) and Outdoor Air (OA) leads to temperature nonuniformity, which may cause operational issues such as coil freezing, control instability, and energy loss. This study experimentally evaluated the performance of static air-mixing devices in a full-scale square duct (1 m × 1 m) under realistic AHU conditions. Three cases were considered: Straightener, Baseline louver mixer, and Orthogonal pattern louver mixer. Mixing effectiveness was assessed using a statistical approach based on temperature distribution, and the pressure drop and mixer efficiency index were used to evaluate the overall performance. The results indicated that the baseline Louver mixer achieved the highest mixing effectiveness (84 – 87%) with a moderate pressure drop (14.7 Pa), whereas the Orthogonal-pattern Louver mixer showed a lower mixing effectiveness (53 – 68%) with a higher pressure drop (34.54 Pa). The Straightener case exhibited limited mixing performance with a negligible pressure drop. These findings indicate that both mixing effectiveness and pressure drop must be considered when evaluating air-mixing devices. This study highlights the importance of performance assessment under realistic operating conditions to improve the energy efficiency of AHU systems.

Keywords

Airmixing performance

Mixing effectiveness

Pressure drop

HVAC duct system

키워드

공기 혼합 성능

혼합 효율

압력손실

공조 덕트 시스템

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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 : 46
No :3
Pages :223-235
Received Date : 2026-04-06
Revised Date : 2026-05-03
Accepted Date : 2026-05-26
DOI :https://doi.org/10.7836/kses.2026.46.3.223

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

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