基于控制载荷法的离心风机单板叶片设计与内部流场分析

发布时间：2018-05-01 22:18

本文选题：离心通风机 + 载荷法　；参考：《上海交通大学》2011年硕士论文

【摘要】：控制载荷法是一种通过控制叶片表面载荷分布方式来设计叶片型线的方法。压力面与吸力面相对速度不同,二者的差值称为叶片载荷,通过控制压力面和吸力面的相对速度或者是其他可以表征载荷分布的物理量的分布即可视为对叶片表面载荷分布的调整。离心通风机常用的叶型主要有单板叶片与中空机翼型叶片。二者相比,中空机翼型叶片气动性能好,效率高,但是结构相对复杂,加工制造成本高,且在空气中杂质颗粒较多的情况下,叶片容易磨损出现漏洞,导致外界杂质进入叶片内部使叶轮转动失衡,影响风机安全稳定运行。单板叶型虽然气动性能相对略低,但是在制造成本、运行稳定性方面具有明显优势。本文以4-72型离心通风机为原型,首先,利用商业流体计算软件对原机翼型叶片叶轮组进行全工况范围内数值模拟,并分析模拟结果,得到其基本的流场特性与性能曲线,发现其流动损失主要是集中在靠近轮盖侧的端部损失。然后,在给定工况下,采用控制载荷法设计出不同载荷加载方式下的单板叶型,并对其流场进行数值模拟,通过对结果的对比分析,表明针对该风机,载荷前加载方式所设计的叶型可以获得性能更好的效率和压升。同时将载荷前加载分布方式下所设计的单板叶片的模拟结果与原机翼型叶片叶轮数值模拟结果进行详细对比,结果证明,在不改变风机叶轮组轮盘、轮盖外形和叶片数目的前提下,利用控制载荷法可以设计出气动性能达到原中空机翼型叶片标准的离心风机等厚度单板叶片,且由于单板叶片其本身结构特点,避免了中空机翼型叶片因磨损而导致叶片破损从而产生叶轮组转动失衡的状况。
[Abstract]:The control load method is a method to design the blade profile by controlling the load distribution on the blade surface. The relative velocities of pressure surface and suction surface are different. The difference between them is called blade load. By controlling the relative velocity of the pressure surface and suction surface or the distribution of other physical quantities which can characterize the load distribution, it can be regarded as the adjustment of the load distribution on the blade surface. The main blade types of centrifugal fan are veneer blade and hollow wing blade. Compared with the latter, the hollow wing blade has good aerodynamic performance and high efficiency, but the structure is relatively complex, the manufacturing cost is high, and the blade is prone to wear and tear loopholes when there are more impurity particles in the air. The impurity enters the blade and causes the impeller to rotate out of balance, which affects the safe and stable operation of the fan. Although the aerodynamic performance of veneer blade is relatively low, it has obvious advantages in manufacturing cost and operation stability. In this paper, the 4-72 centrifugal fan is used as the prototype. Firstly, the commercial fluid calculation software is used to simulate the blade impeller set of the original airfoil in the whole operating condition, and the simulation results are analyzed, and the basic flow field characteristics and performance curves are obtained. It is found that the flow loss is mainly located near the end of the wheel cover. Then, under given working conditions, the veneer blade profile under different load loading modes is designed by using the control load method, and the flow field is numerically simulated. The comparison and analysis of the results show that, The blade profile designed by loading before loading can achieve better efficiency and pressure rise. At the same time, the simulation results of the veneer blades designed under the load pre-loading distribution mode are compared in detail with the numerical simulation results of the original airfoil blade impeller. The results show that, without changing the fan impeller group wheel, On the premise of the shape of the wheel cover and the number of blades, the centrifugal fan blades of equal thickness with aerodynamic performance up to the standard of the hollow wing blade can be designed by using the control load method, and because of the structural characteristics of the veneer blade itself, The wear of the hollow wing blade leads to the breakage of the blade, which leads to the rotating imbalance of the impeller group.
【学位授予单位】：上海交通大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH432

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