Authors

Abstract

Multi-blade centrifugal fans are regarded as an important direction for agricultural cleaning fans due to the advantages of compact structure, low noise and high efficiency. In view of the insufficient aerodynamic performance of traditional centrifugal fans in combine harvester cleaning devices caused by straight-blade structures, as well as the lack of design theory for multi-blade centrifugal fans, this study focused on a multi-blade centrifugal fan with wing-shaped blades. Using a combination of CFD numerical simulation and bench tests, the influence of the volute width-to-diameter ratio on fan performance and the internal flow field was investigated. The results showed that at a rated speed of 1000 r/min, the optimal volute width-to-diameter ratio was 1.3. Compared with the prototype fan, the optimized fan achieved a 7.13% increase in efficiency, a 6.53% increase in air volume, and a 16.63% improvement in air distribution uniformity. In addition, the internal flow of the optimized fan was improved, with reduced turbulence intensity in the tongue region of the volute. Furthermore, a volute width-to-diameter ratio–speed–air volume function model was established using MATLAB, providing a theoretical basis for the selection and design of high-performance multi-blade centrifugal fans.

Abstract in Chinese

多翼离心风机因结构紧凑、低噪高效等优势，被视为农业清选风机的重要方向。针对联合收获机清选装置中传统离心风机因平直叶片结构导致气动性能不足，以及多翼离心风机设计理论缺乏的问题，本研究以翼型叶片的多翼离心风机为研究对象，采用数值模拟与台架试验相结合，探究了蜗壳宽径比对风机性能和内部流场的影响。结果表明：在额定转速1000 r/min下，最优风机蜗壳宽径比为1.3；相较于原型风机，效率提升7.13%，风量提升6.53%，出风均匀性提升16.63%；优化后的风机内部流动改善，蜗舌区域湍流强度减小。基于MATLAB建立蜗壳宽径比-转速-风量函数模型，本研究可为高性能多翼离心风机设计提供选型依据。