多翼离心风机内部流场分析、参数优化及噪声预测

发布时间：2018-06-18 07:07

本文选题：多翼离心风机 + 内部流动　；参考：《华中科技大学》2012年硕士论文

【摘要】：多翼离心风机具有有轮径比大，相对宽度大，叶片数目多的特点，它体积小、噪声低，因此在空调通风等领域得到了广泛的应用，多翼离心风机成为研究的热点对象。而在另一方面，由于多翼离心风机的结构复杂性，各项参数的难以匹配性，如果通过实验的方法，将耗时长，代价大，因此数值计算成为研究多翼离心风机，改善风机性能的一个重要的手段。本文首先对某一实体多翼离心风机模型进行计算，，通过与试验结果对比，验证了计算模型和处理方法的适用性。对多翼离心风机进行三维建模，然后采用Fluent软件对其内部的流场进行计算。全面的分析了某工况下风机内部各个截面的压力和速度分布情况。研究表明，风机内部流动状态非常复杂。研究了气流经过风机各个部件时的速度和压力转换，叶轮、蜗壳以及电机对气流组织的影响。另外，对两种不同工况进行对比分析，分析了它们各个径向面和子午面的压力分布以及蜗壳处的流动情况，蜗壳的设计不合理会引起回流产生，从而影响风机整体的性能。正交试验分析方法是利用正交表来安排与分析多因素试验的一种设计方法，在工程上有很广泛的应用。本文用正交试验的方法分析了叶片数、轮径比、出口安装角、蜗壳宽度这四个参数对风机性能的影响，分别以流量和全压为目标对象，找出了这四个参数对它们的影响大小排名，以及达到最佳效果时的参数组合，并验证了这种组合的正确性。噪声是风机的一个很重要的参数，噪声的大小直接决定着风机的优劣。本文对优化得到的二维风机模型进行噪声分析，得出了指定接收点位置的噪声级大小，并且通过声压频谱特性图，分析出了主要噪声级的频谱范围。
[Abstract]:Multi-wing centrifugal fan is widely used in the field of air conditioning and ventilation because of its large ratio of wheel diameter, relative width, large blade number, small volume and low noise, so multi-wing centrifugal fan has become a hot research object. On the other hand, because of the complexity of the structure of multi-wing centrifugal fan and the difficulty of matching the parameters, if the experimental method is adopted, it will be time-consuming and costly, so the numerical calculation becomes the study of multi-wing centrifugal fan. An important means of improving fan performance. In this paper, the multi-wing centrifugal fan model of a certain entity is first calculated, and the applicability of the calculation model and treatment method is verified by comparing with the experimental results. Three-dimensional modeling of multi-wing centrifugal fan is carried out, and the flow field inside the fan is calculated by fluent software. The distribution of pressure and velocity in each section of the fan is analyzed. The study shows that the flow state inside the fan is very complicated. The effects of impeller, volute and motor on the airflow distribution are studied. In addition, the pressure distribution of the radial and meridian surfaces and the flow situation of the volute are analyzed. The unreasonable design of the volute will cause the backflow and affect the performance of the fan as a whole. Orthogonal test analysis method is a design method to arrange and analyze multi-factor test by orthogonal table. It is widely used in engineering. In this paper, the effects of four parameters, such as blade number, wheel diameter ratio, outlet mounting angle and volute width, on the performance of fan are analyzed by orthogonal test. The influence of these four parameters on their size ranking and the combination of parameters when they reach the best results are found out and the correctness of the combination is verified. Noise is an important parameter of fan. In this paper, the noise level of the optimized two-dimensional fan model is analyzed, and the size of the noise level at the designated receiving point is obtained, and the spectrum range of the main noise level is analyzed through the spectrum characteristic diagram of sound pressure.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH432

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