抓斗式反推装置打开时反推性能参数计算

根据共形映射理论建立了抓斗式反推装置二维流动数学模型,得到抓斗式反推装置打开时反向气流喷射角φ与抓斗式反推装置几何参数间的关联关系.将该模型和涡扇发动机性能计算模型耦合,得到了抓斗式反推装置打开时反推参数的计算模型.以某型涡扇发动机为例,计算了着陆时反推气流角和反推装置几何参数,以及反推力随马赫数、发动机转速的变化关系,并与测量数据进行了对比分析.表明给出的抓斗式反推装置打开时反推性能计算模型具有较好的计算精度.

Mathematical model for calculating effects of target type thrust reverser on turbofan engine performance

The target thrust reverser doors are essentially two-dimensional,and the Mach number of reversed jet is between 0.30 and 0.50.By using the simplifying assumptions of inviscid,incompressible and two-dimensional flows,the flow within target thrust reverser was analyzed.In the analysis,a pair of transformations was used to calculate the ejection angle.According to the transformations,the ejection angle can be expressed as a function of reverser geometric parameters,such as door length,endplate height,door sweep angles and endplate angle.For calculating the actual reverser thrust,the model for calculating ejection angle was combined with the turbofan engine performance model.At last,with this model,the reverser thrust of a turbofan engine was calculated and compared with the test results,showing excellent agreement between them.