论文标题
通过动态模式分解减少模型
Model Reduction via Dynamic Mode Decomposition
论文作者
论文摘要
这项工作提出了一个新的参数复杂系统模型降低框架。该框架采用流行的模型还原技术动态模式分解(DMD),该模式模式分解(DMD)能够基于Koopman操作员理论结合数据驱动的学习和物理成分。在提出的框架的离线步骤中,DMD构建了一个低维量的含量替代量(QOI)的低级别线性替代模型(QOI),这些模型(QOI)源自未知形式的(非线性)复杂的高保真模型(HFMS)。然后,在在线步骤中,在训练参数样本点处的由此产生的本地减少订单基库(ROB)和参数减少订单模型(PROM)被插值以构建一个新的PROM,并使用相应的ROB,用于一组新的目标/测试参数值。插值需要在一致的广义坐标集内的适当歧管上进行。通过线性和非线性问题的数值示例来说明所提出的框架。特别是,与基于投影的正交分解(POD) - PROM和KRIGING的比较证明了它在计算成本和准确性方面的优势。
This work proposes a new framework of model reduction for parametric complex systems. The framework employs a popular model reduction technique dynamic mode decomposition (DMD), which is capable of combining data-driven learning and physics ingredients based on the Koopman operator theory. In the offline step of the proposed framework, DMD constructs a low-rank linear surrogate model for the high dimensional quantities of interest (QoIs) derived from the (nonlinear) complex high fidelity models (HFMs) of unknown forms. Then in the online step, the resulting local reduced order bases (ROBs) and parametric reduced order models (PROMs) at the training parameter sample points are interpolated to construct a new PROM with the corresponding ROB for a new set of target/test parameter values. The interpolations need to be done on the appropriate manifolds within consistent sets of generalized coordinates. The proposed framework is illustrated by numerical examples for both linear and nonlinear problems. In particular, its advantages in computational costs and accuracy are demonstrated by the comparisons with projection-based proper orthogonal decomposition (POD)-PROM and Kriging.