带进气畸变的船用离心风机特性研究

针对船用空调器中的新回风混合畸变对风机性能的影响进行了研究，搭建了模拟试验台，并采用CFD数值模拟分析了不同混合长度、不同风量比对船用离心风机的影响，提出了综合雷诺数、水力半径和混合长度预测混合畸变压力损失数学模型。结果表明，在来流畸变情况下，风机气动效率平均降低6.5%，压力降低约200 Pa；总风量保持不变的情况下，在风量比为5时，风机性能最高，随着风量比继续变大，风机特性近似保持不变。研究结果为空调器风机设计选型时考虑进气畸变的影响提供参考。

Study on the performance of marine centrifugal fan with inlet distortion

Inlet distortion effects on the performance of centrifugal fan in marine air-conditioner caused by new and return air mixing is studied in the paper. An experimental test rig for an industrial fan with similar dual inlets was constructed. The flow fields in the of the centrifugal fan were numerically investigated. A generalized formula considering the Reynolds number, hydraulic diameter, and mixing length was proposed to predict the pressure drop in dual inlets. Results show that the inlet distortion deteriorate centrifugal fan pressure and efficiency by around 200Pa and 6.5%, respectively compared to the uniform flow. Optimum fan performance is achieved at a flow rate ratio of 5 under the same mass flow rate. The increase in the flow rate ratio kept the fan performance almost constant. The results presented in this paper provide advice for design & selection of centrifugal fan under inlet distortion.