Design And Numerical Investigation Of The Inlet Guide Vanes In A Sector Cascade Under Near Stall Condition

Compressor is the core component of aero-engine.It plays an important role in the overall performance and stability.Conner separation tends to happen on the stator and even courses conner stall during operation since there are adverse pressure gradient and lateral pressure gradient in compressor.Conner separation severely disrupts the stability of compressor.As for the experimental investigation of stators under near stall condition,sector/annular cascade is the most typical.Making experiment on the wind tunnel test table has the advantages of low costing and high security.However wind tunnel can only provide smooth airflow.But the infow condition of stators in compressor is much less even,especially under near stall condition.Setting up the inlet guide vanes in front of sector will provide prewhirl inflow and make flow field approach to the compressor.It can also improve experiment reliability and accuracy.In this paper,stator of a modification transonic axial compressor is taken as the research object.Writer uses software NREC for designing the inlet guide vanes.The typical feature of stator flow field is taken as the target of the designing.And a sector cascade is designed in this paper.At first,the numerical simulation of the compressor is carried out between the design condition and near stall condition.The flow field at the design point is compared with that under near condition.The most typical features of flow field under near stall condition are chosen as the targets of the design.Then,the design of the profile of IGV is carried out with the features of inlet flow as the assistant target.But designing result can't make flow field of stator similar with that in compressor.The shape modification of the meridian of the transition section is carried out in this paper.The results show shape modification make the stator satisfy the design requirements.There is separation with large scale in the conner of stator.At last,the sector cascade is designed.And two kinds of suction on the right and left baffle plane are also designed.Simulation results show case SUC2-3%increase the number of stator with conner separation and measurable passages.The relative position between IGVs and stators are changed by making all IGVs rotation of +2° and-2°.The simulation results show that changing the position of IGVs make wake displace.And it also cause different stator occurs conner separation and the distribution of Mach number in the cascade has changed.