Performance Improvement of a Hidden Ceiling Fan

Abstract:

A hidden ceiling-fan is the new design of embedding and hiding itself deeply into the ceiling floor. This design is different from conventional ceiling-fans or circulating fans that usually without an enclosing housing. The majority part of hidden ceiling-fan is embedded in the ceiling floor; hence the enclosing housing will be needed and be created to surround the axial-flow fan. The housing geometric is critical factor for hidden ceiling-fan because the air flow will pass though the horizontal plane of ceiling floor which the inlet and outlet are almost located at same plane. Consequently, the inappropriate design of enclosing housing will cause inhale-return phenomenon. It affects the induced flow performance of a hidden ceiling-fan. Few studies have investigated fan induced flow and its characteristics in a selected space. In this study, computational fluid dynamic (CFD) numerical simulation and experimental investigation were used to predict and valid the flow pattern with different geometric housing and operating conditions. The results showed that the flow pattern has different features as it leaves the fan downward the floor. The unique inhale-return phenomenon probably happens when inappropriate enclosing housing was designed such as high ring-plate and outlet-inlet ratio. Furthermore, the blockage effect will happen if the blockage distance is to short. In conclusion, thissystematic design investigation on hidden ceiling-fan not only provides the fan engineer’s design ability to avoid the inhale-return phenomenon, but also the predicting capability on the air flow induced characteristics and performance.

• Periodical: Applied Mechanics and Materials (Volumes 479-480)
• Pages: 279-283
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.479-480.279
• Online since: December 2013
• Authors: Sheam Chyun Lin, Ming Yuan Hsieh, Cheng Ju Chang
• Keywords: Axial-Flow Fan, Computational Fluid Dynamics (CFD), Flow Pattern, Hidden Ceiling Fan, Inhale-Return Phenomenon

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