Numerical investigation of coil placement angle in condensing units of air-cooled chillers
Subject Areas : Journal of New Applied and Computational Findings in Mechanical Systems
mohsen Talebzadegan
1
*
,
Amin Rabiepoor
2
1 -
2 - Department of Mechanical Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran
Keywords: Chiller, condenser, Convection heat transfer, Axial fan,
Abstract :
The condenser of air-cooled chillers is actually a fin-tube heat exchanger. Generally, the condenser coils have a V-shaped or VV-shaped arrangement with a fan located on top of them. Improper air flow distribution can be considered as an important factor in reducing the performance of the condenser. In this study, an air-cooled condenser with an angle between its coils of 47 degrees was first studied and the velocity, pressure and temperature contours were extracted. In the next step, the performance of the coils was examined by changing the angle between the coils to values of 40, 60, 90, 104, 112 and 120 degrees. Velocity, pressure and temperature contours were also extracted for these condensers. Also, the values of average velocity, average pressure and average heat transfer in the passage of air flow over the coils were examined. The results showed that, assuming the same airflow rate, the V-shaped condensers performed better than the other three samples, and the best performance was for the 120-degree condenser, which increased the average velocity and heat transfer by 17.5% and 38.16%, respectively. On the other hand, the condensers with horizontal coils had the worst heat transfer performance, followed by the condenser with vertical coils.
]1[ دیمی دشت بیاض، م،. ناظري بوري آبادي، ر،. محاسبه بیشینه ضریب عملکردي چیلرهاي سانتریفیوژ در اندازه هاي مختلف چیلردر بارگذاري جزیی، با تغییردرتعداد فن چگالنده، مجله مهندسی مکانیک ،شماره پیاپی ،83 جلد ،48 شماره ،2 ص ص120 ،113- تابستان 1
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