02085nas a2200253   4500008004100000020001400041245011800055210007300173260001600246300001400262490000800276520123400284653003301518653002501551653002001576653003601596653002801632100001701660700001901677700001801696700002401714700002101738856007201759       2023                        eng d  a0898-122100aAn optimisation–based domain–decomposition reduced order model for the incompressible Navier-Stokes equations0 aoptimisation–based domain–decomposition reduced order model for   c2023/12/01/  a172 - 1890 v1513 a<p>The aim of this work is to present a model reduction technique in the framework of optimal control problems for partial differential equations. We combine two approaches used for reducing the computational cost of the mathematical numerical models: domain–decomposition (DD) methods and reduced–order modelling (ROM). In particular, we consider an optimisation–based domain–decomposition algorithm for the parameter–dependent stationary incompressible Navier–Stokes equations. Firstly, the problem is described on the subdomains coupled at the interface and solved through an optimal control problem, which leads to the complete separation of the subdomain problems in the DD method. On top of that, a reduced model for the obtained optimal–control problem is built; the procedure is based on the Proper Orthogonal Decomposition technique and a further Galerkin projection. The presented methodology is tested on two fluid dynamics benchmarks: the stationary backward–facing step and lid-driven cavity flow. The numerical tests show a significant reduction of the computational costs in terms of both the problem dimensions and the number of optimisation iterations in the domain–decomposition algorithm.</p>10aComputational fluid dynamics10aDomain decomposition10aOptimal control10aProper orthogonal decomposition10aReduced order modelling1 aPrusak, Ivan1 aNonino, Monica1 aTorlo, Davide1 aBallarin, Francesco1 aRozza, Gianluigi  uhttps://www.sciencedirect.com/science/article/pii/S0898122123004248