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In this publication, experimental results for the radial multiphase thermal conductivity and the wall heat transfer coefficient of different ceramic sponges as column internals for trickle beds are presented. The experiments were performed in co-current mode with the fluids water and air. The material, porosity and cell density of the sponges were varied. A strong influence of the superficial liquid velocity and of the cell density on the radial multiphase thermal conductivity is found. Dimensionless correlations of the experimental data are given. [ABSTRACT FROM AUTHOR]

Hydrodynamic parameters of ceramic sponges as column internals are investigated using X-ray computed tomography. New qualitative and quantitative insights into multiphase flow in ceramic sponges are gained and a phenomenological study is performed to investigate the flow paths, the hold-up and the effective gas–liquid interfacial area of the trickling liquid inside the sponge packing. The formation of rivulets inside the sponge packing and a redistribution of the liquid at intersections are detected. Additionally, it was observed that the liquid paths inside the sponge start to fluctuate with a higher superficial liquid velocity. A specially designed data processing routine is developed. In the experiments, the test column is operated in co-current (downwards) as well as countercurrent mode with an air–water system. The results are compared to literature data to evaluate the accuracy. The sponges investigated are varied in material, porosity and cell density to obtain knowledge concerning dependencies. The cell density and the superficial liquid velocity turned out to be the significant parameters for the hold-up and the effective gas–liquid interfacial area. [ABSTRACT FROM AUTHOR]

In this publication, experimental results for the radial two-phase thermal conductivity and the wall heat transfer coefficient of different ceramic sponges (variation of material, porosity and pore size) are presented, revealing a strong influence of the superficial air velocity and of the porosity of the ceramic sponges on both the radial two-phase thermal conductivity and the wall heat transfer coefficient. The experimental data are correlated in dimensionless form to offer a “universal” correlation for estimating the radial two-phase thermal conductivity and the wall heat transfer coefficient of sponges in the future. [ABSTRACT FROM AUTHOR]