Abstract: In order to clarify the aerodynamic effects on the turbine caused by the imported large vanes，the whole turbine of a certain engine with a power turbine integrated inter-turbine duct (IITD) was taken as the research object，and the flow field was numerically simulated and researched by means of CFD. The research results show that both on the ground takeoff and max cruise conditions，the imported large vanes in IITD bring obvious effects on the LP turbine and power turbine performance，e.g. 1% magnitude for pressure ratio and power; 2% and 5% magnitude for the axial force of the LP turbine stator and power turbine 1st rotor; 0.5 and 2.5 degrees magnitude for the power turbine 1st stator and 1st rotor. As the operation conditions of the power turbine and exhaust struts are distinct on ground and aerial status，the effect mechanism of the imported large vanes in ITTDs on their aerodynamic loss is different，and thus the aerodynamic loss and efficiency show inconsistent varying trend and magnitude.

Key words: Turbine；Integrated inter-turbine duct；Large vanes；Aerodynamic effects；Ground takeoff；Max cruise

摘要： 为了理清一体化过渡段中大叶片的引入对涡轮部件气动性能和流动情况造成的影响，以带一体化动力涡轮过渡段的发动机的整个涡轮部件为研究对象，通过采用数值模拟的方法对其流动进行了研究。研究结果表明在地面起飞和最大巡航两种发动机工作状态下，一体化过渡段中大叶片的引入对低压涡轮和动力涡轮的性能均有显著影响，膨胀比和功率的影响量级达到1%；低涡动叶和动涡一导轴向力的影响量级分别为2%和5%；动涡一导和动涡一动进口气流角的影响量级分别为0.5°和2.5°。由于地面和空中两种状态下动力涡轮和排气支板的工作状态不同，故一体化过渡段大叶片的引入对其气动损失的影响机理不同，从而造成其损失和效率的变化趋势和量级不同。

关键词: 涡轮；一体化过渡段；大叶片；气动影响；地面起飞；最大巡航