基于正交法的直通篦齿封严齿形几何参数对换热特性影响的试验研究

Orthogonal Design Experimental Investigation of Effect of Tip Geometrical Parameters on Heat Transfer of Straight-through Labyrinth

为研究航空发动机空气系统中封严篦齿的换热情况,针对齿宽、封严间隙、齿高、齿距、前倾角和后倾角等6个影响直通篦齿换热特性的主要几何参数,依据正交原理设计25个不同的直通篦齿试验件,试验研究其对换热特性的影响。结果表明:在试验参数范围内,上述几何参数对对流传热系数的影响趋势有明显的区别,其影响程度由主到次的顺序为:封严间隙→齿距→齿高→齿宽→前倾角→后倾角。封严间隙和齿间距影响非常显著,齿高影响显著,齿宽有一般影响,倾角影响不显著,根据试验结果推断,对流传热系数最小的齿形结构是齿宽为0.1 mm、封严间隙为0.2 mm、齿高为5 mm、齿距为6 mm、前倾角为8°、后倾角为15°。研究结果为高性能封严系统优化设计提供了技术参考。

Experimental investigation of 25 models that are designed according to the orthogonal table to study the influence of the geometry parameters including fin tip thickness t, seal clearance c, fin height H, fin pitch B, front fin taper angle a and back fin taper angle β on heattransfer characteristics of straight-through labyrinth seal at the same pressure ratio. The results show that there are obvious differences between the geometry parameters about the influence on convective heattransfer coefficient. In all of the parameters, the rank of importance on heattransfer characteristics is c→B→H→t→ a→β, C and B affect heattransfer characteristics evidently, His less important t also have certain impact on heattransfer characteristics, while β and a have little influence on it. The geometry for least heat transfer in the test area is t = 0.1 mm, c =0.2 mm, H = 5 mm, B = 6 mm, α= 8°, β = 15°.