直升机发动机入口绕流的数值模拟

对直升机发动机入口处流场采用有限体积法,通过生成贴体结构化网格求解Navier-Stokes(N-S)方程, 进而对MI-171直升机低空悬停和前飞状态进行数值模拟,计算了该型直升机发动机进气道处的流场特性.然后以广义尾流入手,并引入尖涡涡核作用的半经验修正的旋翼自由尾流模型对该机发动机进气道处流场进行计算分析.对沿发动机轴线剖面以及垂至于该轴线剖面的分析结果表明,CFD(Computational Fluid Dynamics)数值模拟方法与旋翼自由尾流分析方法均可以对涡诱导流场进行预测.

Numerical simulation of the flowfield around helicopter engine inlet

To obverse the flow field of a helicopter engine inlet,the finite volume method was adopted and Navier-Stokes(N-S) equation was solved by generating the body-fitted structural grid.The low speed and hovering flight of MI-171 helicopter were numerically simulated,and the flow field characteristic around engine inlet of this helicopter was calculated.Following this,beginning with the prescribed wake model,a semi-empirical correction for the vortex core effect on rotor wake was made and a free wake model was adopted,this method was also used to calculate the flow field characteristic around the engine inlet of this helicopter.From the calculated results paralleling to the engine line and verticalizing to it on engine inlet showed that these two different methods can predict the vortex wake flow field distribution around the helicopter engine inlet.