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A Numerical Analysis on the Optimum Design of a Duct with Multiple Outlets in a Medium Bus  

김민호 (기아자동차)
천인범 (기아자동차)
이대훈 (KMW(주))
Publication Information
Transactions of the Korean Society of Automotive Engineers / v.10, no.4, 2002 , pp. 223-233 More about this Journal
Abstract
The air distribution duct with multiple outlets is an essential part of automotive air-conditioning system In a bus. The estimation of airflow rate in an automotive air-conditioning duct is typically very complicate due to large variations in cross-sectional area and abrupt changes in flow direction, as well as unbalanced distribution of the flow. In this paper, the flow characteristic in a duct with multiple outlets is investigated through experiment, CFD simulation and a one-dimensional simulation. Numerical simulations have been performed for two simplified air conditioning ducts with multiple outlets used in a medium bus. The three dimensional Navier-Stokes code was used to evaluate the overall pressure, velocity Held, and distribution rate at each diffuser according to the change of various design parameters such as ratio of cross-sectional area and radius of bifurcated region. In addition, a one-dimensional program based on Bernoulli equation was developed to obtain optimized diffuser area required to equalize discharge flow rate at each outlet. As a result of this study, optimized diffuser area of design variable by one-dimensional program was very reasonable as compared to the trend deduced from CFD Simulation. Therefore, the simple and convenient one-dimensional analysis developed in this study can be applied in practical design procedure for air-conditioning duct.
Keywords
Air-conditioning duct; Distribution rate; Bernoulli equation; Diffuser; One-dimensional analysis; Design parameters; Bifurcated region;
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Times Cited By KSCI : 1  (Citation Analysis)
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