论文标题
半图像整合和数据驱动的模型订单降低结构动力学与磁滞
Semi-implicit Integration and Data-Driven Model Order Reduction in Structural Dynamics with Hysteresis
论文作者
论文摘要
在许多情况下,已知结构阻尼近似于速率。非依赖速率耗散的流行模型是滞后模型。 Bouc-wen模型是一个非常流行的滞后模型。如果将这种滞后耗散纳入了精制有限元模型中,则数学模型包括通常的结构动力学方程以及非线性非平滑的普通微分方程,用于在高斯点处的大量内部滞后状态,在虚拟工作计算中用于消散。对于此类系统,由于滞后的分布式非分析非线性以及有限元模型中非常高的固有频率,数值集成变得困难。在这里,我们提供两种贡献。首先,我们提出了一种简单的半图像整合方法,在该方法中,结构部分是根据Piché的工作隐式处理的,并明确处理了滞后部分。悬臂梁示例使用高网格细化进行详细解决。收敛非常适合下部阻尼和更平滑的滞后环。对于较不光滑的磁滞回路和/或更高的阻尼,观察到收敛平均线性大致是线性的。令人鼓舞的是,稳定性所需的时间步骤比结构模型的最高固有频率的时间段大得多。随后,使用上述半径方法进行的几个模拟的数据用于构建系统的减少顺序模型,其中将结构动力学投射到少数模式上,并且滞后状态的数量也大大减少。与保留滞后状态数量的误差的收敛研究表现出非常好的结果。
Structural damping is known to be approximately rate-independent in many cases. Popular models for rate-independent dissipation are hysteresis models; and a highly popular hysteresis model is the Bouc-Wen model. If such hysteretic dissipation is incorporated in a refined finite element model, then the mathematical model includes the usual structural dynamics equations along with nonlinear nonsmooth ordinary differential equations for a large number of internal hysteretic states at Gauss points, to be used within the virtual work calculation for dissipation. For such systems, numerical integration becomes difficult due to both the distributed non-analytic nonlinearity of hysteresis as well as the very high natural frequencies in the finite element model. Here we offer two contributions. First, we present a simple semi-implicit integration approach where the structural part is handled implicitly based on the work of Piché, and where the hysteretic part is handled explicitly. A cantilever beam example is solved in detail using high mesh refinement. Convergence is good for lower damping and a smoother hysteresis loop. For a less smooth hysteresis loop and/or higher damping, convergence is observed to be roughly linear on average. Encouragingly, the time step needed for stability is much larger than the time period of the highest natural frequency of the structural model. Subsequently, data from several simulations conducted using the above semi-implicit method are used to construct reduced order models of the system, where the structural dynamics is projected onto a small number of modes and the number of hysteretic states is reduced significantly as well. Convergence studies of error against the number of retained hysteretic states show very good results.