Propagation of Acoustic Waves in Porous Media and their Reflection and Transmission at a Pure Fluid/Porous Medium Permeable Interface

International audienceWe find a sufficient condition of hyperbolicity for a differential system governing the motion of a onedimensional porous medium, so ensuring the existence of a solution for the associated Cauchy problem. We study propagation of linear waves impacting at a pure-fluid/porous-medium interface and we deduce novel expressions for the reflection and transmission coefficients in terms of the spectral properties of the governing differential system. We show three dimensional plots drawing reflection and transmission coefficients as functions of Biot's parameters. In such a way we propose an indirect method for measuring Biot's parameters when the measurement of the reflection and transmission coefficients associated to the traveling waves is possible

About the causes of deactivation of the nickel catalyst methane conversion in the course of its operation

The results of studies of the chemical, phase composition, and structure of the samples of lining materials, and conversion catalysts of natural gas used in the mine unit are outlined. Possible mechanism of nickel ablation from catalyst that caused the reduction of the specific active surface of the catalyst and consequently its activity is described

Toward a Universal Model of Breaking Waves on Shallow Water

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive