热耗散变形下干气密封系统轴向振动稳定性分析

发布时间：2018-06-21 12:52

本文选题：非线性振动 + 干气密封　；参考：《振动工程学报》2016年01期

【摘要】：基于非线性振动理论,建立了气膜-密封环系统轴向振动模型,同时考虑了热耗散有热弹变形对气膜厚度和刚度的影响。在特定的工况下,求解并拟合了非线性气膜的轴向刚度和阻尼,获得了一个非线性受迫振动微分方程。在无外激励情况下,通过求解Floquet指数,讨论了系统分岔的问题,分析了螺旋角对系统稳定性的影响,得到了干气密封系统稳定运行的螺旋角范围,并求得螺旋角为75°54′36″时系统发生Hopf分岔。将数据结果与无热耗散有热弹变形、无变形下的数据进行比较。研究结果表明:考虑热耗散有热弹变形下的系统稳定的螺旋角范围比无热耗散有热弹变形和无变形的螺旋角范围更大。热耗散热弹变形下发生Hopf分岔的分叉点位置相比无热耗散有热弹变形和无变形的分岔点更加突出。这与先前利用龙格-库塔法研究的结果一致,从而验证该方法的正确性。其结果说明,热耗散有热弹变形对干气密封系统的稳定运行有一定的干扰,对工程实际具有一定应用价值。
[Abstract]:Based on the nonlinear vibration theory, the axial vibration model of gas film seal ring system is established, and the influence of heat dissipation thermoelastic deformation on film thickness and stiffness is considered. A nonlinear forced vibration differential equation is obtained by solving and fitting the axial stiffness and damping of the nonlinear film under specific conditions. In the case of no external excitation, the bifurcation of the system is discussed by solving Floquet exponent. The influence of helical angle on the stability of the system is analyzed, and the range of spiral angle of the dry gas seal system is obtained. Hopf bifurcation is obtained when the helical angle is 75 掳54 ~ 36 ". The results are compared with those without heat dissipation and thermoelastic deformation. The results show that the stable spiral angle range of the system with thermal dissipation and thermoelastic deformation is larger than that without heat dissipation and thermoelastic deformation. The bifurcation point with Hopf bifurcation is more prominent than that with no heat dissipation and thermoelastic deformation. This is consistent with the previous results obtained by the Runge-Kutta method, which verifies the correctness of the method. The results show that the thermal elastic deformation of heat dissipation has certain interference to the steady operation of dry gas seal system and has certain application value to engineering practice.
【作者单位】：兰州理工大学石油化工学院;
【基金】：国家自然科学基金资助项目(51165020)
【分类号】：TB42

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