火箭推进

通过Jeffcott转子建立了转子初始弯曲结构模型,推导了初始弯曲转子的振动响应,仿真分析了弯曲因子和初始弯曲相位角对转子振动响应的影响,总结了初始弯曲转子的振动特性和规律。在理论分析的基础上,开展具有初始弯曲的压气机转子运行试验,分析了该初弯转子的振动特性,对比了平衡状态对该初始弯曲转子响应的影响。结果表明:初弯转子起动时的响应幅值等于初始弯曲幅度,响应初始相位与初始弯曲相位大小相等,方向相反; 初始弯曲不会改变转子的临界转速,但会影响转子的共振幅值和相位,只有初始弯曲相位角为0°或180°时,共振相位才等于90°; 初始弯曲对刚性转子或准柔性转子振动的影响较大,而对柔性转子振动的影响相对较小; 初弯转子在某一转速区内响应振幅会出现一“凹坑”,初始弯曲相位角越接近180°,“凹坑”底部对应的振幅越小; 初弯转子响应幅值“凹坑”对应的转速范围随着平衡精度的提高而向高速区移动,当“凹坑”对应的转速范围落于共振转速区内时,转子的共振峰值可降至最低。

The structural model of an initial bending rotor was established by Jeffcott rotor,and the vibration response was derived.After simulating and analyzing the influence of curvature factor and initial bending phase angle on the rotor vibration response,the rotor vibration characteristics and response rules were summarized.On the basis of theoretical analysis,the rotor running test of compressor with initial bending was carried out.The vibration characteristics of this rotor were analyzed,and the influence of balancing state on the response of this initial bending rotor was studied.The results indicate that the response amplitude of the initial bending rotor at startup is equal to the initial bending amplitude,and the response phase at startup is equal to the initial bending phase while the direction is opposite.The initial bending does not change the critical speed of the rotor,but it affects the resonance amplitude and phase.The resonance phase is equal to 90° only when the initial bending angle is 0° or 180°.The initial bending has a great influence on the vibration of rigid or quasi-flexible rotor,but a relatively small influence on flexible rotor.The response amplitude of the initial bending rotor will appear a pit in a certain speed zone,and the closer the initial phase angle is to 180°,the smaller the amplitude corresponding to the pit bottom.The speed range corresponding to response amplitude pit of the initial bending rotor moves towards the high speed zone with the improvement of balance accuracy.When the speed range corresponding to the pit falls within the resonance speed zone,the resonance peak of the rotor can be reduced to the lowest.

引言
1 初始弯曲转子建模
2 初始弯曲转子振动分析
3 初始弯曲转子运行试验
4 结论

图1 初始弯曲转子示意图<br/>Fig.1 Schematic diagram of the initial bending rotor

图1 初始弯曲转子示意图
Fig.1 Schematic diagram of the initial bending rotor

图2 振动幅值和相位随初始弯曲相位角变化曲线(r-0=0.5)<br/>Fig.2 Curves of vibration amplitude and phase change with initial bending phase angle(r-0=0.5)

图2 振动幅值和相位随初始弯曲相位角变化曲线(r-0=0.5)
Fig.2 Curves of vibration amplitude and phase change with initial bending phase angle(r-0=0.5)

图3 振动幅值和相位随弯曲因子的变化曲线(α0=180°)<br/>Fig.3 Curve of vibration amplitude and phase change with bending factor(α0=180°)

图3 振动幅值和相位随弯曲因子的变化曲线(α0=180°)
Fig.3 Curve of vibration amplitude and phase change with bending factor(α0=180°)

图4 转子结构示意图<br/>Fig.4 Diagram of rotor structure

图4 转子结构示意图
Fig.4 Diagram of rotor structure

图5 叶轮螺纹安装引起转子初始弯曲示意图<br/>Fig.5 Diagram of rotor bending caused by the installation of impeller threads

图5 叶轮螺纹安装引起转子初始弯曲示意图
Fig.5 Diagram of rotor bending caused by the installation of impeller threads

表1 转子径向跳动量<br/>Tab.1 Radial runout value of rotor

表1 转子径向跳动量
Tab.1 Radial runout value of rotor

图6 压气机转子前三阶振型<br/>Fig.6 First three vibration modes of compressor rotor

图6 压气机转子前三阶振型
Fig.6 First three vibration modes of compressor rotor

图7 初次升速转子振动位移曲线<br/>Fig.7 Displacement curves of the rotor vibration during the initial speed up

图7 初次升速转子振动位移曲线
Fig.7 Displacement curves of the rotor vibration during the initial speed up

图8 一次平衡后转子振动位移曲线<br/>Fig.8 Displacement curves of the rotor vibration after primary balancing

图8 一次平衡后转子振动位移曲线
Fig.8 Displacement curves of the rotor vibration after primary balancing

图9 二次平衡后转子振动位移曲线<br/>Fig.9 Displacement curves of the rotor vibration after secondary balancing

图9 二次平衡后转子振动位移曲线
Fig.9 Displacement curves of the rotor vibration after secondary balancing

图10 平衡完成后转子振动位移曲线<br/>Fig.10 Displacement curves of the rotor vibration after the balancing is completed

图10 平衡完成后转子振动位移曲线
Fig.10 Displacement curves of the rotor vibration after the balancing is completed

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备注

引言

1 初始弯曲转子建模

2 初始弯曲转子振动分析

3 初始弯曲转子运行试验

4 结论

期刊信息