本文主要分析迴轉式壓縮機之消音罩的消音特性，其數值模型利用聲學模組ANSYS Acoustic ACTx R15.0進行聲場分析。其目的在建立一套有限元素分析方式應用於壓縮機消音罩之研發，並提供消音罩改善設計的方向，使設計者在事前可對消音罩進行消音分析與研究。 文中主要分為兩個部分，第一部分為波導管連接消音罩模型，假設出口為開放性邊界條件之設定並將實際實驗量測之模型匯入ANSYS聲學模組進行分析，比較實驗結果時以空氣為聲音傳導介質且以傳遞損失作為主要消音性能評估之指標，實驗結果與數值模擬結果趨勢相同。第二部分為消音罩設計，為探討消音罩本身之內部聲場，將出入口波導管皆移除，模擬時以R22a冷媒為聲音傳導介質且以噪音衰減作為主要消音性能評估之指標。 ;This research focused on the noise reduction characteristics of the muffler in a rotary compressor. A finite element software, ANSYS Acoustic ACTx R15.0, was used to obtain the mathematical solutions. This research was split up into two sections. At the beginning, the muffler was connected to waveguides with anechoic outputs in the simulation model. The introduction of waveguides is to guarantee the existence of plane sound wave in the calculation of Transmission Loss (TL). The acoustic medium is air. Then, an experiment was performed. The numerical results and experimental results compare well if the output boundary of waveguides was chosen the open boundary. The second part of the research is the study of a real muffler without waveguides. The acoustic medium R22a. Another index, Noise Reduction (NR), was adopted to assess the noise reduction performance. A parameter study of various geometric parameters was reported. Design suggestions of the muffle were also given.
