Radial heat transport in a fixed-bed reactor made of metallic foam pellets: Experiment and particle-resolved computational fluid dynamics. (15th November 2022)

• Record Type: Journal Article
• Authors: George, Ginu R.; Bockelmann, Marina; Schmalhorst, Leonhard; Beton, Didier; Gerstle, Alexandra; Lindermeir, Andreas; Wehinger, Gregor D.
• Is Part Of: International journal of heat and mass transfer. Volume 197(2022)
• Publication Date: 2022-11-15
• Subjects: Open-cell foam -- CFD -- Heat transfer -- Fixed-bed reactor; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2022.123376
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Heat transfer characteristics studied for packed bed of metal foams. Validated particle-resolved CFD model reveal detailed insights. Correlations developed for heat transfer in bed of metal foams. Metal foam pellets show large potential for low to medium flow rates. Abstract: Open-cell metallic foams in the shape of pelletized catalysts are regarded as potential catalyst substrates for the application in fixed-bed reactors. This work reports an experimental study and a detailed Computational Fluid Dynamics (CFD) model to investigate the heat transfer performance of a fixed-bed reactor made of open-cell metallic foam pellets. The steady-state heat transfer behavior of a hot gas flowing through such a packed bed under wall-cooled conditions was examined. The proposed CFD model is in line with the particle-resolved CFD (PRCFD) approach that accounts explicitly for the random packing structure, so that the transport processes in the interstitial regions are fully resolved. The momentum and energy transports inside the highly porous foam particles are considered by closure equations based on the porous-media model. The Rigid Body Dynamics (RBD) method is adopted to create the packing geometry. The axial temperature and the pressure drop obtained by the CFD simulations show good agreement with experimental data. To evaluate the thermal performance, effective heat transport parameters in a packed bed such as the effective radial thermal conductivity and the apparent wall-fluid heat transfer coefficient are determined, with the aid of a 2D pseudo-homogenous plug-flow reactor model. The correlations for heat transport characteristics as a function of particle Reynolds number for the metallic foam packed bed are also presented. Graphical abstract: Image, graphical abstract