涡轮出口气流角对低速风力引射器流场影响的数值研究

Numerical Research on Effects of Turbine Outlet Flow Angle on Aerodynamic Performance of Wind-Ejector of Low-Speed Wind Turbine

为了开发先进的具有广泛适用性的低速风力涡轮,采用涡扇发动机喷管引射技术设计了双涵道风力涡轮,以新型低速引射式风力涡轮的引射混合器为研究对象,采用CFX商用软件基于RANS方程和k-Epsilon湍流模型,数值研究了涡轮出口气流角对风力引射器混合性能的影响。研究结果显示,涡轮出口气流与轴向夹角由0°增至30°,引起了波瓣后侧流向涡量迁移,最大正交涡量降低了1/3,波瓣内侧中部分离对涡与槽道吸力侧分离区汇合,风力引射器内流道总压损失从2.4%增大至5%,此夹角大于10°时外流场对称结构消失并失稳。

The turbofan engine nozzle ejector technology was adopted to design a high-efficiency low speed wind turbine with the double bypass for a broader areas in the world. The aerodynamic characteristics of the windejector of the new wind turbine were numerically researched on turbine outlet flow angle changing based on Reynolds-averaged NS equations and k-Epsilon turbulence model,using commercial software CFX. Results show that,as the angle between turbine outlet flow and the rotation axis increased from 0°to 30°,the positive vorticity of the stream-wise vortice pairs migrated to the negative vorticity,the maximum normal vorticity was gradually reduced by 1/3,the separation vortex pairs adhesion of the lobes were gradually forced to mix with the separation vortices near the suction surface of the channels,the total pressure loss in the lobes of the wind-ejector increased from 2.4% to 5%,and if the angle was greater than 10°,the flow stability of the wind turbine outflow field rapidly disappeared.