風機消聲器的設計及機理研究

隨著人們生活水平的日益提高，噪聲在人們的工作和生活中越來越受到關注。其中風機的噪聲尤為突出，已經對人們產生了巨大的負面影響。怎樣有效地降低風機的噪聲具有重要意義和應用價值。
通過對風機噪聲源進行分析，控制噪聲最有效的措施就是在風機出口管安裝消聲器。比較現有消聲材料的優缺點，本文提出了利用納米碳酸鈣基天然乳膠復合材料這一新型消聲材料來提高風機消聲器的性能。
本文首先以天然乳膠為基體，納米碳酸鈣粒子作為研究對象，制備不同納米碳酸鈣含量復合材料試樣。對新型材料的力學性能和斷口進行實驗分析，選出性能最好的比例配置。實驗結果表明，納米碳酸鈣含量為 10%時，復合材料取得抗拉強度和扯斷伸長率的最好效果。
通過分析風機的主要噪聲頻率，在有限元理論和聲波方程的基礎上，來選擇新型復合材料制成的不同消聲結構，并分析了材料厚度、孔徑大小和穿孔率對消聲結構共振頻率的影響。仿真結果顯示，復合材料的厚度對其共振頻率影響很大，隨著厚度的增加，共振頻率越高，最大位移越小。
最后通過聲學實驗驗證了新型材料的降噪效果。結果顯示，新型復合材料具有良好的消聲降噪效果，具有良好的應用前景。
關鍵詞：
風機，消聲器，模態分析，復合材料，Ansys
Abstract
With people living standard is increasing,noise has more and more attention in the woke and life of people. Fan noise isespecial, it has caused tremendous negative impact to our life. So it is of great significant and social value to reduce the noise effectively.
By the analysis of fan noise source, themost effective way to control the noise is to install the fan muffler in theoutlet. Compared with the existing noise elimination aterial,this paper put forward enhance the performance of muffler by the new composite material of natural rubber latex and nano- CaCO3. This paper use natural rubber latex as the substrate material, preparation composite materials of different content of nano- CaCO3.By analysis of the mechanical property nd SEM of the composite material, choose the proportion of best performance. he results showed that when the content of nano- CaCO3 was 10%,the tensile strength and elongation at break are the best. Select different ilence structure by made of the new composite material by analyzing the main noise frequencies based on Finite Element Methodand acoustical equation. And analysis of the aterial thickness, pore size andperforation rate on the impact of resonance frequency of silence structure.Simulation results show that the thickness of the composite material greatly affect its resonant frequency, with increasing thickness, the higher the resonance frequency, the smaller the maximum displacement. Finally, experimental verification of acoustic noise reduction effect of the new material. The results show that the new composite material has goodoise reduction with a good prospect.
Keyword: Fan, Muffler, Modal Analysis, Composite Material, Ansys