模态应变能在反应堆及一回路系统动力分析中的应用
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摘要
为对系统级模型中不同部件和设备动力贡献程度进行量化考察,提出了一种基于模态应变能的计算方法。应用该方法对2个工程案例进行了分析。首先对某堆型反应堆冷却剂系统波动管支吊架位置变更导致的地震响应较大变化的原因进行了分析。分析发现,波动管局部主导模态由于支吊架位置变化而发生变化,主导频率所对应的输入地震响应谱位置相应变化,进而影响了波动管附近的地震响应。然后,本文对同堆型环路模型动力分析中蒸汽发生器主蒸汽管是否能从环路模型中解耦进行了论证。分析发现,根据USNRC SRP3.7.2解耦准则的第二条,主蒸汽管满足解耦条件,可在动力分析中单独进行处理。本文所提出的分析方法可定量反映部件和设备在系统模型中的动力贡献程度,模态应变能的计算仅应用了系统级模型的质量和刚度信息,无需对整个系统进行时程瞬态分析。
In order to investigate the dynamical contribution of individual component and equipment in system-level models, this study proposed a computational method based on the modal strain energy(MSE). Two engineering case studies applying the MSE method are demonstrated herein. The first study investigates the main reason causing large seismic response change of a prototype reactor coolant system(RCS) surge pipe due to the location change of surge suspension device. The analysis shows that the local dominant mode of the surge pipe is altered by the location change of the suspension. Such change of dominant resonant frequency leads to a significant change at the corresponding frequency of input seismic response spectrum,thereafter affects the dynamical response. The second case study discusses the decoupled strategy of the main steam-pipe from the loop model for separated dynamical analyses. MSE analysis, together with the second decoupling criteria suggested by USNRC SRP 3.7.2, justifies this deed. Modal strain energy(MSE) method proposed in this paper is able to quantify the dynamical contribution of components and equipment from the system-level dynamical analysis models. The computation of MSE only utilizes the system-level model stiffness and mass matrices. No time-domain transient analysis is necessary.
In order to investigate the dynamical contribution of individual component and equipment in system-level models, this study proposed a computational method based on the modal strain energy(MSE). Two engineering case studies applying the MSE method are demonstrated herein. The first study investigates the main reason causing large seismic response change of a prototype reactor coolant system(RCS) surge pipe due to the location change of surge suspension device. The analysis shows that the local dominant mode of the surge pipe is altered by the location change of the suspension. Such change of dominant resonant frequency leads to a significant change at the corresponding frequency of input seismic response spectrum,thereafter affects the dynamical response. The second case study discusses the decoupled strategy of the main steam-pipe from the loop model for separated dynamical analyses. MSE analysis, together with the second decoupling criteria suggested by USNRC SRP 3.7.2, justifies this deed. Modal strain energy(MSE) method proposed in this paper is able to quantify the dynamical contribution of components and equipment from the system-level dynamical analysis models. The computation of MSE only utilizes the system-level model stiffness and mass matrices. No time-domain transient analysis is necessary.
引文
[1]曹树谦,张文德,萧龙翔.振动结构模态分析[M].天津:天津大学出版社,2001,21-25.
[2]BREHM M,ZABEL V,BUCHER C.An automatic mode pairing strategy using an enhanced modal assurance criterion on modal strain energies[J].Journal of Sound and Vibration,2010,329:5375-5392.
[3]USNRC.SEISMIC SYSTEM ANALYSIS SRP 3.7.2Rev.3[S].2007.
[2]BREHM M,ZABEL V,BUCHER C.An automatic mode pairing strategy using an enhanced modal assurance criterion on modal strain energies[J].Journal of Sound and Vibration,2010,329:5375-5392.
[3]USNRC.SEISMIC SYSTEM ANALYSIS SRP 3.7.2Rev.3[S].2007.