An improved mean streamline loss model for splittered centrifugal/mixed-flow compressor impellers is presented. One-dimensional model predictions, CFD simulations and experimental results for Krain impeller are compared to confirm the model validity. A new description for the interaction between blade number and splitter blade length of a splittered mixed-flow compressor impeller with high hub/tip ratio is discussed and formulized. The optimal principal blade number and optimal splitter blade length corresponding to maximum impeller efficiency are selected by the new formulas studied. The results indicate that the improved model and new formulas have reasonable prediction effects for the impeller efficiency and the selection of blade number and splitter blade length. Blade height/pitch ratio can also be adopted as a selection reference especially for high hub/tip impellers. Effective blade number or equivalent solidity is only suitable for evaluating load capacity rather than efficiency in impeller design processes.

中文翻译：

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基于改进损失模型的分流混合流压缩机叶轮叶片数选择

提出了一种改进的分流式离心/混流压缩机叶轮平均流线损失模型。比较了Krain叶轮的一维模型预测，CFD模拟和实验结果，以确认模型的有效性。对轮毂/叶尖比高的分流式混流压缩机叶轮的叶片数与分流叶片长度之间相互作用的新描述进行了讨论并提出了新的描述。通过研究的新公式选择与最大叶轮效率相对应的最佳主叶片数和最佳分流叶片长度。结果表明，改进的模型和新公式对叶轮效率，叶片数量和分流叶片长度的选择具有合理的预测效果。叶片高度/螺距比也可以用作选择参考，特别是对于高轮毂/叶轮。有效叶片数或等效强度仅适用于评估负载能力，而不适合叶轮设计过程中的效率。