空气清新机用多翼离心风机的改进设计研究

【作者】 张力；

【导师】 席德科；

【作者基本信息】 西北工业大学 ， 流体机械及工程， 2006， 硕士

【摘要】 本文主要是对空气清新机用多翼离心风机的改造设计研究。多翼离心风机既是空气清新机的关键核心部件,亦在空调通风、电器设备等的散热冷却中有着十分广泛的应用。本次改进设计的目的就是提高多翼离心风机的效率,增大空气清新机的风量,降低噪声(或至少保持原噪声不变)。 首先对空气清新机原型机及其配套的前向多翼离心风机进行了分析研究和试验测试。其次对多翼离心风机传统设计方法进行了分析研究:指出了这种设计方法对结构参数的选择有很大的不确定性;采用这样的方法进行设计时往往导致多种设计方案;要想在多方案之中筛选出好的方案须做大量的模型试验工作。在分析传统设计方法的基础之上提出改进方案:a.利用四次贝赛尔曲线对风机的叶片型线进行设计,并在设计好的型线上加NACA0012翼型;b.为了改善蜗壳内的流动,减少旋涡损失,在蜗壳内布置栅格;c.还对蜗舌长度和叶片数进行了优化选择。改进方案的优劣比较和优选是通过大量的数值模拟完成的。最后对改进后的空气清新机整机和单独离心风机进行了实验验证,实验结果与数值模拟吻合较好,误差在3%以内;并与原型机的试验数据进行了比较,结果表明,改进后的空气清新机的性能比原型机优良,达到了改进要求。更多还原

【Abstract】 The paper presents the redesign study of the multi-blade centrifugal fan for the air freshing machine. Multi-blade centrifugal fan is not only the key part of the air freshing machine but also is applied widely in air-conditioner and ventilation for cooling wiring. The aim of this paper is to improve the efficiency of the fan, increase the quantity of air, but reduce the yawp (or keep the yawp) of the air freshing machine.Firstly, analysis and test have been carried out to assess the prototype of air freshing machine and its forward multi-blade centrifugal fan. Secondly, based on the analysis of the traditional design method of the multip-blade centrifugal fan proposals are made on the uncertainty of the tradition method for the selection of construct parameters, variety scheme due to the uncertainty, and a great deal of work needed to find out the optimal design scheme. This paper provides the advanced design scheme: (1). applying biquadratic bezier curve to frame the blade model line with addition of NACA0012 aerofoil;(2). grids layout in the helishell to streaming the flow and reduce the vortex loss;(3).the optimization applied on the length of snail tongue and the number of the blade. Abundant numerical simulations have been employed to help to Compare and select the optimal scheme. Finally, experimental test has been carried out on the air freshing machine and its centrifugal fan separately. Satisfied agreement has been achieved on the numerical results and experimental dates. As a consequence, comparison of the testing results of the improved fan with the prototype shows that the improvement of the performance.更多还原