A hyper-reduction method using adaptivity to cut the assembly costs of reduced order models

At every iteration or timestep of the online phase of some reduced-order modelling schemes for non-linear or time-dependent systems, large linear systems must be assembled and then projected onto a reduced order basis of small dimension. The projected small linear systems are cheap to solve, but assembly and projection become the dominant computational cost. In this paper we introduce a new hyper-reduction strategy called reduced assembly (RA)...