【作者】 宫延明；

【导师】 金涛；

【作者基本信息】 浙江大学 ， 化工过程机械， 2008， 硕士

【摘要】 随着人民对自身保健的意识逐渐增强,许多病人需要定期或经常吸氧,来调节体内对氧气的需求。家庭保健型制氧机应运用而生,它逐渐开始替代传统的小氧气瓶。虽然保健型制氧机有所发展,但也存在比较大的缺点,那就是噪音问题,因此降低制氧机的噪声就必然要对制氧机的噪声分析和振动研究提出更严格的要求,本文研究工作的目的是降低保健制氧机的噪声,研究结果对提高产品质量有很重要的意义,从而提高产品的竞争力。本文首先对国内外医用保健制氧机的技术现状,无油压缩机噪声的机理、传播途径以及噪声抑制的方法进行了综述阐明。然后在ANSYS软件平台下建立制氧机壳体结构有限元模型,应用有限元的方法对其的外壳体进行了结构模态分析,声模态分析,声固耦合模态分析,得出其固有频率,不同厚度下的制氧机有限元模型的固有频率,并模拟制氧机在无油压缩机工作情况下的结构动力谐响应分析,得出响应曲线,找到共振频率。并在SYSNOISE软件平台下应用边界元方法对制氧机壳体声固耦合模型的辐射噪声进行研究,通过设置流体边界条件,吸声边界条件,制氧机的场点,计算出其整体辐射噪声,对其ATV声传递向量进行结算,得出其单元贡献度,对了解其噪声传递路径有很大帮助,有利于提出相应的降噪方法。最后运用近场声全息的手段对小型制氧机进行试验研究,明确了试验目的,设计了试验方法,并应用先进的噪声振动检测仪器完成了数据的采集,然后应用SenSound软件对数据进行分析,得到了制氧机的整个表面的声辐射声强,声速,声压,声压级等声学特征信号,接下来对制氧机的整体降噪方案进行研究,并通过实验验证了降噪方案的可行性。更多还原

【Abstract】 Nowadays people’s self health protection consciousness is gradually rising up, a lot of patient need absorbing oxygen at a periodical time or all the time for adjusting the human body’s requirement of the oxygen. Family health care oxygen generator came out and began to substitute the traditional air tank. Although health care oxygen generator has been developing for some time, there are some big shortcomings in exist which is the noise problem. Therefore the problem of reducing the noise of the oxygen generator must bring forward the very strict demand for the analysis on the noise and vibration research of the oxygen generator. This article’s research aim is to reduce the oxygen generator’s noise. Research results are very meaningful to get the improvement of the product’s quality therefore it can increase the competitive ability of the product.At first his article makes a full description on technology situation of the domestic and overseas’ medical health care oxygen generator, the mechanism of the oil-free compressor’s noise, the transmitting approach and way on how to suppress the noise. Then through the software ANSYS we build the 3-D FE model to do the structural modal analysis, acoustic modal analysis and coupling model between acoustic and structure analysis by finite element methods (FEM). We get the natural frequency and the natural frequency at the oxygen generator’s different thickness and also simulate the humorous responses analysis under the situation when the oil-free compressor works, get the responses curve graph and sympathetic vibration frequency.Through the software SYSNOISE we use the boundary element methods (BEM) to do the research on the entire shell’s noise radiation of oxygen generator. By setting up the fluid boundary condition sound absorbing boundary condition, oxygen generator field point, we calculate the entire body’s noise radiation and do the analysis on the ATV acoustic transmission vector, get the element contributive analysis. It will do a great help for our knowing the noise transfer path, and it will be propitious for us to put forward the noise reduction methods.At last the article uses the near-field acoustic holography methods to do the research on the minitype oxygen generator. We clarify the experiment purpose and design the experiment methods and apply the advanced noise vibration measuring device to accomplish the data acquisition, and then apply the SenSound software to process the date analysis. We get the acoustic radiation signal such as sound intensity, sound velocity, sound pressure, sound pressure level of the oxygen generator’s entire surface and then do the research on the entire oxygen generator’s noise reduction methods. Though the experiment we test and verify the noise reduction methods’ practicability.更多还原