摘要
建立了热变形下气膜-密封环系统角向摆动计算模型,考虑热变形对特例下的气膜温度场分布的影响,计算动环变形量,用Maple软件拟合得到变形后的气膜厚度,继而对角向刚度和阻尼进行拟合,得出的非线性受迫振动方程包含二次项、三次项,计算Floquet指数,对系统进行稳定性分析,求解Melnikov函数研究系统的混沌问题,得知外激励大小不变时,动力系统发生混沌运动的难易程度与阻尼大小呈负相关关系,求解出能够使系统稳定运行的螺旋角范围,当螺旋角为75°10′43″时系统发生Hopf分岔.结果表明,考虑热变形时,混沌现象及螺旋角的范围较不考虑热变形时都有一定变化,即热变形对系统的稳定运行有一定影响,在干气密封优化方面有实际的应用价值.
A calculation model of angulation swing of gas film-seal ring system in the case of thermal deformation is established. The influence of thermal deformation on temperature field distribution of gas film is considered to calculate the deformation amount of the moving ring. The gas film thickness after deformation is obtained by means of fitting with software Maple. The angulation stiffness and damping are then fitted, so that a nonlinear forced vibration equation with quadratic and cubic terms is obtained. The Floquet index is calculated to analyze the stability of the system. The chaos problem is studied by solving Melnikov function and it is found that when the size of the external excitation is unchanged, the difficulty degree of occurrence of chaotic motion of dynamic system will exhibit negative correlation with the magnitude of the damping. The helix angle range that can make the system operation stable is found, Hopf bifurcation will occur when the helix angle is 75°10′43″. The result shows that when the thermal deformation is considered, the range of the chaotic phenomena and the helix angle will have a certain change, namely the thermal deformation will have a certain influence on the stable operation of the system and will also have a practical application value in connection with dry gas seal optimization.
作者
韩明君
李芳芳
王伟兵
丁雪兴
马连生
HAN Ming-jun;LI Fang-fang;WANG Wei-bing;DING Xue-xing;MA Lian-sheng(School of Science,Lanzhou Univ.of Tech.,Lanzhou730050,China;School of Petrochemical Engineering,Lanzhou Univ.of Tech.,Lanzhou730050,China)
出处
《兰州理工大学学报》
CAS
北大核心
2019年第2期166-172,共7页
Journal of Lanzhou University of Technology
基金
国家自然科学基金(51165020
11472123)
甘肃省高等学校科研项目(2015A-045)
关键词
热变形
非线性
温度场
混沌运动
稳定性
thermal deformation
nonlinearity
temperature field
chaotic motion
stability
