中文摘要：

为研究不同的导流罩对冰箱冷凝风机噪声的影响,利用数值模拟的方法对风机在不同导流罩下的流动特性进行仿真,得到不同导流罩下风机后缘涡流的分布,获取风机出口的湍流强度的变化特性,并进行相关的分析.通过试验验证表明,使用封闭式导流罩时风机在较宽频带上的噪声都较使用半开式导流罩时高;封闭式导流罩下风机出风湍流强度更高,衰减速度更快,噪声也更大;使用半开式导流罩时风机无论单独测试还是装机测试都可获取更低的噪声.同时,通过数值模拟和测试的方法分析半开式导流罩的宽度对冰箱冷凝风机出口的湍流强度以及冰箱噪声的影响,得到风机噪声最低时的导流罩宽度.冰箱冷凝风机在半开式导流罩下产生的湍流强度较低,相应的冰箱噪声也较低.

英文摘要：

In order to study the effect of the deflecting ring on the noise generated by axial fan for condenser in refrigerator,numerical method is used in the simulation of the flow field generated by axial fan with different deflecting rings.Vortex exists in the gap between blade top and deflecting ring has been acquired and characteristics of turbulence intensity in outlet of fan have been analyzed.Some conclusions have been acquired with experimental results.Compared with the semi-open type deflecting ring,noise level of fan with closed type deflecting ring is much higher at multiple frequency bands; Turbulence intensity and its decreasing rate in outlet of fan are much higher; Noise levels of single fan and refrigerator are decreased when semi-open type deflecting ring is used.In addition,effect of length of semi-open type deflecting ring on turbulence intensity and noise of refrigerator has been researched,and optimal length for lowest noise level is acquired.Better flow and noise performance will be obtained when axial fan for condenser in refrigerator is with semi-open deflecting ring.