Three-dimensional numerical investigation were carried out to investigate the flow-field in the passage between support struts in front of the axial-flow fan with the help of the commercial code EURANUS

which is an integral part of the software package NUMECA FINE.It was found that the support strut had significant impact on the axial-flow fan performance.The optimization design was performed for the support strut based on numerical result and flow analysis.In addition

three-dimensional flow analysis was carried out to verify the performance improvement of the newly optimized support strut.It was found that with the new strut the efficiency of the fan is improved over the entire range of mass flow

the losses are locally reduced and the flow in the passage between the support struts becomes more reasonable.