In this paper, a type of novel projection-based, time-divided reduced order model (ROM) is proposed for dynamic fluid-structure interaction (FSI) problems, where spatial and temporal dimensions are partitioned as follows: spatially, each kind of variable is separated from others in terms of its attribution (fluid/structure), its category (velocity/pressure) and its component (horizontal/vertical); temporally, basis functions are deliberately adopted in small time windows tailored through extensive numerical trials. By the combination of space and time decompositions, the proposed ROM enables prolonged simulations under prescribed accuracy thresholds. Numerical experiments are carried out by means of a numerical comparison between the proposed ROM and corresponding full-order model (FOM) on solving a benchmark problem of FSI with a vibrating elastic beam in the fluid flow, where the representation of basis function sets on perturbation parameters is investigated as well. Extensive numerical results demonstrate the accuracy and efficiency of the proposed ROM. The developed numerical techniques are dimension-independent, which can be seamlessly extended to high dimensional FSI problems.

翻译：本文针对动态流固耦合问题，提出了一种新颖的基于投影的时分降阶模型。该模型在空间维度上，依据变量属性（流体/固体）、类别（速度/压力）及分量（水平/垂直）对各变量进行分离；在时间维度上，通过大量数值试验，在精心选取的小时间窗内采用基函数。通过空间与时间分解的结合，所提降阶模型能在预设精度阈值下实现长期模拟。数值实验将所提降阶模型与对应的全阶模型进行对比，求解了弹性梁在流体中振动的基准流固耦合问题，同时研究了基函数集对摄动参数的表示能力。大量数值结果表明，所提降阶模型具有较高的精度与效率。所发展的数值技术具有维度无关性，可无缝扩展至高维流固耦合问题。