Zhou Wenjie, Wei Xuesong, Wang Leqin, Wu Guangkuan
School of Energy and Power Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
Institute of Process Equipment, Zhejiang University, Hangzhou 310027, People's Republic of China.
R Soc Open Sci. 2017 May 31;4(5):161059. doi: 10.1098/rsos.161059. eCollection 2017 May.
Solving the static equilibrium position is one of the most important parts of dynamic coefficients calculation and further coupled calculation of rotor system. The main contribution of this study is testing the superlinear iteration convergence method-twofold secant method, for the determination of the static equilibrium position of journal bearing with finite length. Essentially, the Reynolds equation for stable motion is solved by the finite difference method and the inner pressure is obtained by the successive over-relaxation iterative method reinforced by the compound Simpson quadrature formula. The accuracy and efficiency of the twofold secant method are higher in comparison with the secant method and dichotomy. The total number of iterative steps required for the twofold secant method are about one-third of the secant method and less than one-eighth of dichotomy for the same equilibrium position. The calculations for equilibrium position and pressure distribution for different bearing length, clearance and rotating speed were done. In the results, the eccentricity presents linear inverse proportional relationship to the attitude angle. The influence of the bearing length, clearance and bearing radius on the load-carrying capacity was also investigated. The results illustrate that larger bearing length, larger radius and smaller clearance are good for the load-carrying capacity of journal bearing. The application of the twofold secant method can greatly reduce the computational time for calculation of the dynamic coefficients and dynamic characteristics of rotor-bearing system with a journal bearing of finite length.
求解静平衡位置是转子系统动态系数计算及进一步耦合计算的重要组成部分。本研究的主要贡献在于测试超线性迭代收敛方法——双重割线法，用于确定有限长度滑动轴承的静平衡位置。本质上，通过有限差分法求解稳定运动的雷诺方程，并采用复合辛普森求积公式强化的逐次超松弛迭代法获得内部压力。与割线法和二分法相比，双重割线法的精度和效率更高。对于相同的平衡位置，双重割线法所需的迭代步数总数约为割线法的三分之一，不到二分法的八分之一。完成了不同轴承长度、间隙和转速下平衡位置和压力分布的计算。结果表明，偏心率与偏位角呈线性反比关系。还研究了轴承长度、间隙和轴承半径对承载能力的影响。结果表明，较大的轴承长度、较大的半径和较小的间隙有利于滑动轴承的承载能力。双重割线法的应用可大大减少具有有限长度滑动轴承的转子-轴承系统动态系数和动态特性计算的计算时间。
