Influence Of Elliptic Tubercle Leading Edge Blade Modification In Linear Compressor Cascade

With the development of gas turbine technology,more and more high requirements are put forward for the compressor load.As one of the important parts of the compressor,the performance of the blade is directly affected by the performance of the gas turbine.The leading edge,as the starting position of the blade surface layer,has a great influence on the flow in the cascade channel.The reasonable design and optimization of the front edge can effectively control the flow separation,improve the structure of the flow field in the gate,and improve the aerodynamic performance of the compressor blade.In this paper,this paper takes the high cross section of the 5%leaves of the DMU37 leaf as the research object.Through the reconstruction of the front edge and the shape line stacking,the elliptical front edge and the front edge of the drum are combined to form a compound front edge modification.The effect and the mechanism of the compound modification on the flow of the original cascade are explored and compared through the calculation and comparison of the different control parameters.Find the optimal leading edge modification parameters.The CFD method of grid independence and experimental checking is used to calculate the different working conditions of the prototype cascade.The results show that the loss impact angle distribution of the prototype cascade is similar to that of the different flow Maher numbers,and the flow condition is better at the negative impact angle.With the increase of the punching angle,the position of the front saddle point is biased toward the side of the blade pressure surface and the reverse pressure gradient of the suction surface.The separation structure changes at the near end wall,and the separation flow range expands along the transverse and suction surface of the end wall,and the loss increases.The effects of the two leading edge structures on the flow field and loss distribution are different.The elliptical front edge can reduce the cascade loss effectively at the different punching angles.The mechanism is that the oval front edge can eliminate the large range reflux region from the beginning of the 0 punching angle to the near end wall and increase the flow area of the middle diameter of the cascade.At the same time,the loss of partial leaf height is reduced.At the same time,due to the accumulation of low energy fluid to the end area,the separation degree of the end wall is aggravated,the flow is deteriorated and the end wall loss increases.After the punching angle is greater than a certain value,the radial scale of the reflux area can be further reduced on the basis of the elliptical front edge,so that the whole body loss is further reduced and two kinds of leading edge pairs can be reduced.The aerodynamic performance of cascade is greatly improved by superposition of the optimization effect of flow field.