叶片出口角对翼扇型农用清选风机性能的影响OA

The centrifugal fan is a key component of the air-and-screen cleaning system in combine harvesters,and its performance significantly impacts the cleaning efficiency.Currently,the majority of agricultural fans in China use simple straight blades,which result in suboptimal performance and low efficiency.Multi-blade fan is an important direction for future agricultural cleaning fans,but there is relatively little research in the field of agricultural machinery applications,and there is a lack of corre-sponding reference basis.Eight sets of multi-blade fan impeller models with different blade outlet angles were constructed.Based on CFD numerical simulation method,wind speed,total pressure,and total pressure efficiency were used as experimental indicators.The influence of different blade outlet angles on the hydraulic characteristic curve,cross-sectional velocity,and vortex distribution map of the multi-blade agricultural cleaning fan was collected and analyzed.The most effective impeller model was used for bench testing.The results show that when the blade outlet angle increases from 56.0°to 73.5°,the uniformity of the internal flow field of the fan increases,the flow separation phenomenon weakens,and the surface airflow velocity of the blade increases.The efficiency of the fan reaches a maximum of 73.01%in the range of 70.0°to 73.5°.The consistency of the simulation results has been verified through bench tests.This study can provide a reference for the independent design of multi-blade agri-cultural cleaning centrifugal fans in China.