ABSTRACT In axial fan simulation using multiple reference frame (MRF) method, an inappropriate size of rotating zone may affect the accuracy of results. In order to study the influence of axial and radial sizes in a wide flow rate range, five rotating zone sizes were investigated at seven flow rate points from 0 to 11.3 m3/s in a simplified fan setup configuration. Comparing the fan characteristic curves, it is found that the accuracy of simulation results is sensitive both to axial size and radial size, and the sensitivity varies with flow rates. In order to accurately predict the fan performance, it is recommended that the MRF rotating zone be long enough to cover the rotating backflow and pre-rotation area upstream the fan for prediction at low flow rates, and the radial size of MRF zone be large enough to include the trailing vortexes for prediction at middle to high flow rates. While the other sizes are not very influential, as long as the integrity of the blades is included.

中文翻译：

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轴流风机模拟中磁流变区划分策略

摘要 在使用多参考系（MRF）方法的轴流风机模拟中，不合适的旋转区尺寸可能会影响结果的准确性。为了研究轴向和径向尺寸在较宽的流速范围内的影响，在简化的风扇设置配置中，在从 0 到 11.3 m3/s 的七个流速点上研究了五种旋转区域尺寸。对比风机特性曲线，发现仿真结果的精度对轴向尺寸和径向尺寸均敏感，且敏感度随流量变化。为了准确预测风机性能，建议 MRF 旋转区足够长，以覆盖风机上游的旋转回流和预旋转区域，以便在低流速下进行预测，并且 MRF 区的径向尺寸足够大，以包括尾涡，以便在中高流速下进行预测。而其他尺寸影响不大，只要包括刀片的完整性即可。