轴流压缩机基元级叶片前后缘修正的造型方法研究

Study on modeling method for modifying pre-edge and post-edge of axial-flow compressor blade with elementary stage

轴流压缩机的工作环境十分复杂,为了保证在大攻角下的良好气动性能,通常在完成基元级造型后,需要对基元级叶型的前后缘作必要的修正,即用圆弧来代替尖缘。要求圆弧必须同时与吸力面与压力面相切。圆弧半径一般按经验数据选取。在这一过程中,通常采用逐点搜索的方法来最终确定这两个切点。由于这种逐点搜索方式十分复杂,从而导致巨大的计算工作量。为了克服传统的逐点搜索方法计算量大的缺点,运用解析几何的方法,对这一问题进行了深入的分析,将给基元级叶片加前后小圆的几何问题转化成了一个二元非线性方程组,并详细给出了推导过程及求解方法。

Axial compressor working environment is very complex.In order to ensure good aerodynamic performance under the large angle of attack,necessary amendments to pre-edge and post-edge of elementary blade profile shall be done usually after the completion of elementary-level modeling,which is to replace the sharp edge with arc.The arc must be tangent with the suction side and pressure side.And the arc radius is selected generally based on empirical data,in which the two cut points shall be confirmed finally through point by point searching method,which is very complicated,a huge amount of calculation may occur.In order to overcome the traditional shortcomings of large calculation,further analysis on this problem is carried out it with the application of analytic geometry,in which geometric problem of adding pre and post circular arcs to blade with elementary stage is converted into a binary nonlinear equations system,and the derivating process and solving method are provided in detail.