几何参数对涡轮低压导向器变工况性能的影响

在低速风洞上,对某型弹用涡扇发动机涡轮低压导向器原型和改型进行了变工况条件下的详细流场测量。与原型低压导向器相比,改型低压导向器多种几何参数发生了改变,主要包括采用优化的子午型线、正弯叶片、后部加载叶型以及前缘负冲角设计等,因此二者的冲角特性有较大差异。实验分别对两种导向器叶栅测量了3种工况条件,分别为正冲角工况、设计工况和负冲角工况,并对结果进行了对比分析。实验结果显示:改型不仅在设计工况下能量损失较小,而且具有较好的攻角适应性,表现为在所测工况范围内叶栅出口总压损失随工况的变化幅度很小,而原型出口损失则对冲角敏感,损失变化幅度相对较大。

Effects of Geometry Parameters on Incidence Characteristics of Turbine Low Pressure Guide Vane

Experimental measurements were performed in a low speed wind tunnel for both original and modified turbine LGV's which are used in turbofan engines under different operating conditions.Compared with the original design,the modified design changed many geometry parameters,including adopted optimizing meridional endwall profile,positively curved blade,aft-loading airfoil and negative incidence angle at the leading edge,so the incidence characteristics of these two designs differ significantly.The two LGV's were measured at three operating conditions,i.e.positive incidence,design and negative incidence operating conditions.Results show that the modified design not only has smaller energy loss,but also has better incidence angle adjustability,which means that with the change of operating conditions total pressure loss alters smaller in the range of three operating conditions.Exit loss of the original design is sensitive to the incidence angle and varies greatly.