本論文以三台國內外知名品牌之室內送風機為樣本，進行改善風機整體噪音的研究，為了尋找所有可能的噪音源，在研究中我們將三台送風機之馬達互換，並更改吸音措施，以觀察、測試各配件對送風機整體噪音值的貢獻度，進而抑制噪音的產生與傳遞。以往的研究常將噪音分為結構噪音與氣動傳音兩種噪音源，本論文提出的方法是於送風機的回風口處加裝一只消音箱，重點是，可在不影響送風機效能之前提下，有效的抑制送風機之氣動噪音，使送風機整體的噪音量大為降低。

ABSTRACT
In this article, the noises generated by fan coils from the three major brands in the market were studied. To analyze and find out the possible sound sources, the sound attribution of different parts was measured. After several experiments, the authors inspect that the aero acoustic noise can be reduced by a silencer. Therefore, specific silencers were designed and installed at the inlet of fan. Experimental results demonstrate that the aero acoustic noise level can be reduced greatly by the specially designed inlet silencer.

Keyword: noise reduction, silencer, aero acoustic noise.

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