拉力式对转桨扇发动机的建模与性能评估

Modeling and Assessment of a Contra-RotatingPuller Propfan Engine

关键词:  桨扇发动机  对转桨扇  建模  性能评估  仿真

Key words:  Propfan engine  Contra-rotating propfan  Modeling  Assessment  Simulation

摘要:

为了分析桨扇发动机的总体性能，为桨扇发动机的预研工作提供方案，建立了一种三轴拉力式对转桨扇发动机的仿真模型，将桨扇发动机看成桨扇和涡轴发动机匹配的结构。桨扇建模基于相似原理，从单排桨扇的气动性能入手，并考虑了桨扇轮毂的影响以及前后排对转桨扇的相互影响和空气流道的收缩，模型与实验数据的误差在2%以内。核心机建模采用三轴涡轴部件级模型。基于该模型进行了桨扇发动机的性能评估。结果表明，桨扇和进气道的耦合作用对发动机性能影响很小，可以忽略。桨扇轴距半径比对发动机性能有一定影响，可以设置在0.4～0.6以内。前后排桨距角始终保持为56°，当高度增加时，总推力下降、sfc上升。当马赫数增加时，总推力先下降再上升，sfc先上升后下降。桨距角是重要的性能调节参数，4°的桨距角变化量可以带来64%的推力变化。

Abstract:

In order to analyze the performance of propfan engines to provide methods for beforehand research， a simulation model of three-shaft contra-rotating puller propfan was proposed. Propfan engine was considered as a match with propfan and turboshaft. Propfan model， based on the similitude principle， starts with the aerodynamic performance for a single rotating propfan. The influence of hub， the interaction of contra-rotating propfans and the contraction of stream are all considered. Error of the model and the experimental results is no more than 2%. The core engine model is a component-level model of a three-shaft turboshaft. Assessments are conducted based on the model. The propfan-inlet interaction has a little influence on performance and could be ignored. The wheelbase of contra-rotating to radius ratio may have an impact on performance and could be set up from 0.4 to 0.6. When the pitch angles are both 56°， the thrust would decrease and sfc would increase if the height grows up. If the Mach number grows up， sfc would increase first and then decrease， and the thrust would decrease first and then increase. The pitch angles of propfan are important regulative parameters for engine performance. When the variations of pitch angles are 4°， the thrust will change 64%.