Title: Scale-bridging within a complex model hierarchy for investigation of a metal-fueled circular energy economy by use of Bayesian model calibration with model error quantification

Abstract: Chemical reactor network (CRN) modeling is a promising approach for scale-bridging within a model hierarchy covering a huge range of scales from micro to macro in the scope of developing an innovative metal-fueled circular energy economy. This holds if valid information from CRNs, being models of reduced complexity, can be obtained on a much denser set of operating conditions than available from experiments and elaborated simulation methods like Computational Fluid Dynamics (CFD). An approach for CRN calibration including model error quantification from recent literature is used for developing a CRN model of a laboratory reactor for flash ironmaking, using data from the literature. By introducing a meta model of a CRN parameter, it has been possible to calibrate a simple CRN model on an extended set of operating conditions with satisfactory results. This way, the employed coupled calibration and uncertainty quantification framework seems promising for the task of scale-bridging in the model hierarchy under investigation. Challenges for the further extension of the present work into that direction are discussed.