In this work, we analyze Parametrized Advection-Dominated distributed Optimal Control Problems with random inputs in a Reduced Order Model (ROM) context. All the simulations are initially based on a finite element method (FEM) discretization; moreover, a space-time approach is considered when dealing with unsteady cases. To overcome numerical instabilities that can occur in the optimality system for high values of the P\'eclet number, we consider a Streamline Upwind Petrov-Galerkin technique applied in an optimize-then-discretize approach. We combine this method with the ROM framework in order to consider two possibilities of stabilization: Offline-Only stabilization and Offline-Online stabilization. Moreover, we consider random parameters and we use a weighted Proper Orthogonal Decomposition algorithm in a partitioned approach to deal with the issue of uncertainty quantification. Several quadrature techniques are used to derive weighted ROMs: tensor rules, isotropic sparse grids, Monte-Carlo and quasi Monte-Carlo methods. We compare all the approaches analyzing relative errors between the FEM and ROM solutions and the computational efficiency based on the speedup-index.
翻译:在这项工作中,我们分析了在减序模型(ROM)背景下随机输入的分流最佳控制问题。所有模拟最初都基于一种有限元素方法;此外,在处理不稳的个案时,还考虑了空间时间办法;为了克服P\'eclet 数字高值最佳系统中可能出现的数字不稳定性,我们考虑了一种在优化和分解方法中应用的精简上风Petrov-Galerkin技术。我们将这种方法与ROM框架结合起来,以考虑两种稳定的可能性:离线稳定和离线稳定;此外,我们考虑随机参数,并在分解方法中采用加权的正正正正调分解位算法来处理不确定性的量化问题。我们采用几种四方技术来获取加权ROM:变压规则、异性稀释网格、蒙特-卡洛和准蒙特-卡尔洛方法。我们比较了基于FEM和ROM速度计算的所有方法之间的相对差错。我们比较了基于FEM和速度计算方法的模型和ROM解决方案。