摘要 离心风机是一种在工业生产中提供气体动力的流体机械，在国民经济的各个行业中应用都非常广泛。离心风机内部的流动形态十分复杂，在运行的过程中常常伴随着容积损失、机械损失以及流动损失等现象，这些现象会使得离心风机的工作效率降低。随着我国对能源问题的重视，用户对离心风机的气动性能有了更高的要求。本文以9-19型离心风机为研究对象，利用数值模拟法对风机内部流场进行了研究。在此基础上，以提高离心风机的工作效率为目标，对离心风机的叶片进行了优化设计。主要的研究工作如下： 本文利用FLUENT软件对9-19型离心风机进行了全工况数值模拟，对比离心风机的试验数据，数值模拟法的方案是具有可靠性的。另外，在最佳工况下，对风机的内部流场进行分析，结果发现：离心风机内部气体流动不均匀，叶片流道中存在着流动分离、涡流的现象，这些现象致使离心风机的工作效率降低。 通过公式推算，发现叶片数目与叶片出口安装角度对离心风机的性能有较大影响，以这两个因素为待优化的几何参数，对叶片进行优化设计。首先确定出最佳的叶片数目，然后在此基础上，确定出最佳的叶片出口安装角度，最终，对最佳的叶片数目进行验证。经过多组的数值模拟计算，得到了叶片的优化模型。计算结果表明：当叶片数目为16片，叶片出口安装角度为时，离心风机内部气体的流动状况得到了改善，流动损失的现象有所减少，而且离心风机的全压和效率都得到了显着的提高。当流量为1264时，风机的效率最高，在这个工况点下，优化模型的风机与原风机相比，全压提高了231.55Pa，而效率则提高了4.95%。最后，文中还对优化模型进行了静力分析，经过校核，优化模型的叶轮满足强度要求。 关键词：离心风机；数值模拟；叶片优化；静力分析 Abstract Ce
ntrifugal fa
n is a commo
n fluid machi
ne which provides e
nergy of gas i
n i
ndustrial productio
n. It is widely used i
n various i
ndustries of
natio
nal eco
nomy. The i
nter
nal flow of ce
ntrifugal fa
n is very complex, a
nd there are volume loss, mecha
nical loss a
nd flow loss i
n the process of operatio
n, which will reduce the efficie
ncy of the ce
ntrifugal fa
n. With the atte
ntio
n to e
nergy problem, users have higher requireme
nts for the aerody
namic performa
nce of ce
ntrifugal fa
n. I
n this paper, the flow field i
n 9-19ce
ntrifugal fa
n was researched by
numerical simulatio
n. A
n optimizatio
n desig
n method was proposed to improve the efficie
ncy of the ce
ntrifugal fa
n based o
n ce
ntrifugal fa
n
numerical simulatio
n.The mai
n work a
nd co
nclutio
ns of the paper are as follws: I
n this paper, the 9-19ce
ntrifugal fa
n was simulated by FLUENT software, compared with the experime
ntal data of ce
ntrifugal fa
n, the method of
numerical simulatio
n is reliable. I
n additio
n, u
nder the best co
nditio
n, the i
nter
nal flow field of the fa
n was studied a
nd a
nalyzed. The results show that the i
nter
nal flow of the ce
ntrifugal fa
n is u
neve
n, a
nd there are flow separatio
n a
nd eddy curre
nt i
n the blade passage, resulti
ng i
n the low efficie
ncy of the ce
ntrifugal fa
n. Based o
n the formula calculatio
n, the
number of blades a
nd the blade outlet i
nstallatio
n a
ngle have great i
nflue
nce o
n the aerody
namic performa
nce of ce
ntrifugal fa
n. Taki
ng above two factors as the geometric parameters to be optimized, the optimizatio
n desig
n of the blade is carried out. First, optimized the
number of blades a
nd selected the best
number of blades. The
n, o
n this basis, optimized the blade outlet i
nstallatio
n a
ngle a
nd selected the best a
ngle. Fi
nally, the best
number of blades was verified. After several groups of
numerical simulatio
n, the optimal model of blade was obtai
ned. The calculatio
n results show that whe
n the
number of blades is 16 a
nd the blade outlet i
nstallatio
n a
ngle is, the i
nter
nal flow field of the ce
ntrifugal fa
n has bee
n improved, a
nd the flow loss has bee
n reduced, i
n additio
n, the total pressure a
nd efficie
ncy of the ce
ntrifugal fa
n are sig
nifica
ntly improved. Simulatio
n results show that the efficie
ncy of ce
ntrifugal fa
n is the highest whe
n the flow rate is 1264, at this worki
ng co
ndito
n, compared with the origi
nal fa
n, the total pressure of the optimized model fa
n is i
ncreased by 231.55Pa, while the efficie
ncy is i
ncreased by 4.95%. Fi
nally, the static a
nalysis of the optimizatio
n model was carried out. After checki
ng, the impeller of the optimizatio
n model meets the stre
ngth requireme
nts. Keywords: Ce
ntrifugal fa
n; Numerical simulatio
n; Blade optimizatio
n; Static a
nalysis 目录 摘要I Abstract III 目录V 第1章绪论1 1.1研究背景及意义1 1.2国内外研究现状2 1.2.1离心风机内部流场特性的研究2 1.2.2离心风机的性能优化研究5 1.3本的主要研究内容8 第2章离心风机的简介11 2.1引言11 2.2离心风机的主要结构11 2.3离心风机的工作原理及特性参数13 2.4本章小结15 第3章离心风机数值模拟的基本理论17 3.1引言17 3.2基本方程17 3.2.1质量守恒方程17 3.2.2动量守恒方程18 3.2.3能量方程19 3.3湍流模型20 3.3.1标准模型20 3.3.2模型21 3.4转动区域和静止区域的求解21 3.5本章小结22 第4章离心风机内部流场的三维数值模拟23 4.1离心风机物理模型的建立23 4.2网格划分25 4.3计算方法与边界条件25 4.4网格无关性验证26 4.5数值模拟结果验证与内部流场分析27 4.5.1数值模拟结果验证27 4.5.2内部流场分析28 4.6本章小结30 第5章离心风机叶片优化设计31 5.1引言31 5.2叶片数目对离心风机性能的影响31 5.3叶片出口安装角度对离心风机性能的影响32 5.4离心风机的叶片优化34 5.4.1叶片数目的优化34 5.4.2叶片出口安装角度的优化35 5.4.3叶片优化方案验证37 5.5优化结果分析39 5.6本章小结42 第6章离心风机叶轮的有限元分析45 6.1引言45 6.2离心风机叶轮的模型与材料属性45 6.3加载求解与结果分析47 6.4本章小结49 第7章总结与展望51 7.1主要结论51 7.2展望52 参考文献53 攻读硕士期间已发表的59 致谢61 第1章绪论 1.1研究背景及意义 工业风机广泛用于冷却、通风、抽真空和除尘、充气等，并且风机占全球工业能源需求的很大一部分。离心风机广泛用于这些应用，因为其成本低，易于制造，坚固耐用，压力比高，风量较大[1]。离心风机是工业生产中提供气体动力的流体机械，在国民生活中具有重要的作用，但由于国内现有技术水平的限制,离心风机的工作效率较低，并消耗着我国大量的电能[2]，根据相关资料统计，离心