某民用大涵道比涡扇发动机风扇缩尺试验件气动性能数值仿真

Numerical simulation of aerodynamic performance of scaled fan of a civil high-bypass-ratio turbofan engine

根据某民用航空发动机大涵道比风扇1/2缩尺试验任务的需求,利用三维数值模拟软件对该风扇缩尺试验件各个转速下的内、外涵气动性能进行了数值仿真分析,并对缩尺几何、弹性恢复角及涵道比等参数对风扇缩尺试验件内、外涵气动性能的影响进行了对比分析.结果表明:该风扇缩尺试验件各转速下的内、外涵性能都基本达到设计指标;几何缩尺分别引起了风扇外涵、内涵设计点的效率分别降低了1.26%,0.77%;80%转速下,叶尖弹性恢复角减小0.36°使风扇外涵稳定工作裕度扩展了4.04%,但近设计点总压比和效率均有所衰减;双涵道风扇在不同涵道比状态下,内、外涵相互影响,流量-总压比及流量-绝热效率特性是在一定范围内的曲线带.

According to the testing demand for the half-scaled fan of a civil high-bypass-ratio turbofan engine,the aerodynamic performance of scaled fan was simulated using three-dimensional CFD software.The effects of geometry scale,elastic recovery angle and bypass-ratio on the performance of the fan were also analyzed.The numerical simulation results show that the design objectives for the scaled fan can be met basically under all kinds of corrected rotating speed.When the geometry of the fan was scaled down to the half,the adiabatic efficiency of the bypass and core passages decrease by 1.26% and 0.77%,respectively.Under 80% corrected rotating speed,0.36 degree reduction of the elastic recovery angle at fan tip could expand the stall margin by 4.04%,while the total pressure ratio and the adiabatic efficiency decreased at near design point.The total pressure ratio-mass flow characteristic and adiabatic efficiency-mass flow characteristic of the bypass and core passages for turbojet engine were represented a band of curves within a certain scope,under the bypass-ratio effect.