Optimize Design And Experimental Study The Dual-Stage Radial Vanes Swirler

With the development of the modern aircraft engine combustion chamber,the swirler is widely used,the swirler has become the most important part of the combustion chamber,its performance directly affects the performance of the combustion chamber.The swirler as a strong vortex generator,there will be intense turbulence pulsation happen within it,and the mutual shearing action of airflow which between the secondary swirler and primary swirler aggravated the complexity of the flow.There are numerous of Key design parameters in the swirler,strong mutual coupling action between parameters,the detail structure design of the swirler which greatly influence the internal flow characteristics.In order to study the influence of detail structure design of the swirler on the downstream flow field,reveals the influence law of key structural parameters of the swirler,this paper carried out the details of the different structure parameters of the numerical simulation research,comparative analysis of the swirler under different structural parameters of the downstream flow field characteristics,according to the results of numerical analysis of benchmark optimization design was carried out on the the swirler,and used the PIV to test and verify the flow field of optimized swirler.In this paper,the research directions including the effect of venturi type,vanes thickness,width of the secondary swirler vanes,the size of ring channel,mixing length and Sleeve structureThe results showed that:(1)when the venturi surface by flat deformation for the contraction,the swirler downstream of the velocity distribution changed little,and when the venturi surface by flat deformation for the expansion of form,axial velocity and radial velocity will be increased,and the tangential velocity will be reduced.Using flat venturi has the longest of the center reflux area,adopting closed shortest venturi tube center reflux area expansion form,but the radial size will increase.Closed expansion form of a venturi tube is helpful to increase the strength of the recircul,increasing the the area of center recirculation zone.2)Within a certain range of the vanes thickness variation has a little influence on the downstream flow field of the swirler.3)Increase the width of the secondary swirler vanes the axial velocity and radial velocity will be increased,tangential velocity will be reduced,the center recirculation zone size and backflow intensity increases.4)Increases the size of ring channel,the axial velocity and radial velocity decreased,the tangential velocity increases,the backflow zone size bigger,but the backflow intensity is reduced.5)Increase the mixing length,the peak of axial velocity will be increased,less tangential velocity,the velocity distribution is more close to the center.With the increase of the mixed length,axial length and radial dimensions of the recirculation zone are decreased,backflow strength will be weakened.6)Sleeve structure has a great influence on the downstream flow field of the swirler.The angle and the length of Sudden expansion sleeve has a great influence on the center recirculation zone,and circular sleeve has obvious stick wall effect.7)the optimal swirler is obtained,the flow field of center recirculation zone is full and symmetrical,test and numerical results are in good agreement.