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ADPI Characteristics of Line Diffuser in a Room with Perimetric Heating Load  

Cho Young-Jin (신뢰성분석연구센터)
Kang Seok-Youn (한양대학교 대학원 기계공학과)
Moon Jong -Sun (한양대학교 대학원 기계공학과)
Lee Jae-Heon (한양대학교 공과대학 기계공학부)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.16, no.12, 2004 , pp. 1204-1211 More about this Journal
Abstract
It is difficult to apply a conventional selection guide for diffusers when the diffuser is installed in a perimeter zone, because the air diffusion performance index (ADPI) vs. throw/length (T/L) ratio curve listed in conventional guide does not consider the perimetric heating load through the walls. The objective of this study is to evaluate the effect of the perimetric heating load on the ADPI and propose a selection guide for a proper line diffuser when perimetric heating load exists. The velocity and temperature distributions and the ADPI values are obtained numerically with various heat load ratios and air flow rates. The velocity and temperature distributions and the ADPI values are analyzed by CFD in case of various heat load ratios and air flow rates. Also, ADPI was calculated by those results. The ADPI values by numerical results are compared with an existing experimental data to verify the method for the evaluation of ADPI proposed in a present study. In case of a line diffuser installed at the high side wall, the ADPI decreases according to the increases of the flow rate on every heat load ratio of the present study except 0.75. The ADPI vs. T/L ratio curves have been proposed for the heat load ratios of 0.25, 0.5, 0.75 to guarantee the comport thermal environment when diffusers are installed in perimeter zone.
Keywords
ADPI; Throw distance; Characteristic length; Heat load ratio; EDT; T/L ratio;
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  • Reference
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