文档介绍：华中科技大学硕士学位论文 I摘要随着生活水平的提高和消费观念的更新,轴流风机作为家用空调器室外机风机,其噪声、流量、效率等性能指标倍受人们关注。本文利用商用CFD软件对室外机的内流场进行了模拟,研究各几何参数对室外机流场和声场的影响;采用Lighthill声比拟法对轴流风扇的气动噪声进行了预测,研究该方法在轴流风扇噪声预估方面的可靠性。具体工作包括两个方面:首先,根据厂家提供的空调器室外机的结构装配图和性能指标,建立了合理的室外机箱体及其零部件的CFD计算模型,为后续优化室外机结构提供了理论依据和模拟试验基础,并在此基础上进行了风道系统的改进研究。其次,利用商用CFD软件Fluent对室外机轴流风扇进行了噪声数值预估,为实验得出的两轴流风扇之间噪声特性的差异提供了一些理论依据,同时实验研究也验证了数值模拟的合理性和有效性。整篇论文共分为5个章节,第1章-绪论,论述了轴流风机数值模拟及其实验研究的国内外进展情况;第2章-空调器室外机轴流风扇叶尖涡研究,采用三维N-S方程、κ-ε方程湍流模型和SIMPLE算法,对基于多部件耦合的空调器轴流风扇叶尖涡的三维流动特性进行了数值分析。第3章-空调器室外机轴流风扇的气动噪声数值预估,主要研究叶轮表面作为噪声源时的频谱分布特性和内流结果,为低噪声轴流风扇的设计提供参考;第4章-噪声测量试验研究,实验结果为数值模拟提供了校核依据;第5章-空调器室外机风道系统改进研究,运用试验和CFD方法,优化空调风道系统的流道结构。关键词:空调器室外机轴流风扇 CFD 气动噪声华中科技大学硕士学位论文 IIAbstract With the advance of standard of living and the renovate of consume concept, the technical indexes, like noise, flow rate, and efficiency for axial flow fans which are installed in the air-conditioner outdoor set, receive great attention in the design. In this paper, the inner flow field of the outdoor set is simulated mercial CFD software-Fluent to study the influence on its flow field and acoustic field caused by the various geometric parameters. The aeroacoustic noise is forecasted by using Lighthill acoustic analogy method, and the reliability of this method to forecast the aeroacoustic noise of the axial fan is discussed also. The particular works contain two aspects: First, based on the assembly drawing and performance target of the air-conditioner outdoor set which is supplied by the manufacturer, a reasonable putational model of the outdoor set with ponents has been built. This provides a theoretical foundation and the basis of numerical simulation for optimizing the structure of the outdoor set later. On this basis, the improvement of its duct system has been carried out. Second, the aeroacoustic noise of the axial fan is simulated by mercial CFD software-Fluent. The results are analyzed to provide some theoretical basis for the differences of the noise characteristic obtained from experi