泵喷推进器线谱非定常推力预报方法与试验验证

Line spectrum unsteady thrust prediction method and test verification of pump jet

为预报泵喷推进器转子与周期性前导叶尾流互作用线谱非定常推力,忽略泵喷推进器转子叶片厚度,将泵喷转子简化为环形叶栅,根据片条理论,在半径r处截取泵喷转子分段,忽略流场参数沿分段径向的变化,从而可将该环形叶栅分段视为平面叶栅,在平面叶栅与简谐波互作用的基础上考虑周期性进流,推导得到前导叶分段与转子分段互作用线谱非定常激振力,转子分段周向积分得到非定常推力线谱预报公式,通过数值和试验方法验证公式的有效性。开展设计参数影响分析,得到当前导叶-转子间距与前导叶弦长的比值大于1时,转子-后导叶间距对转子单个叶片的激振力线谱推力几乎不存在影响。

In order to predict the unsteady thrust of the interaction line spectrum of the pump jet propeller rotor and the periodic leading vane wake,ignored the thickness of the pump jet propeller rotor blades,and simplified the pump jet rotor into an annular cascade.According to the sheet theory,the radius that is the segment of the pump jet rotor was intercepted at r,and the change of the flow field parameters along the segment radial was ignored.Therefore,the annular cascade segment can be considered as a planar cascade,and the periodic inflow is considered based on the interaction between the planar cascade and the harmonic wave.The unsteady excitation force of the interaction line spectrum between the front guide vane segment and the rotor segment is derived.The unsteady thrust line spectrum prediction formula is obtained through the circumferential integration of the rotor segment.The validity of the formula is verified through numerical and experimental methods.A design parameter impact analysis was conducted,and it was found that when the ratio of the current guide vane rotor spacing to the chord length of the front guide vane is greater than 1,the rotor rear guide vane spacing has almost no impact on the excitation force line spectrum thrust of a single rotor blade.