Mathematical modeling of the motion of a portion of helium under pulsed injection over a fixed bed of cenospheres

Abstract

A mathematical model is constructed and an analytical solution is obtained for the problem of a onedimensional steady flow of a mixture of different gases with hollow permeable particles. The case of a one-dimensional unsteady flow of such a mixture is analyzed numerically. The numerical solutions are compared with experimental data on the motion of the peak concentration of helium in a fixed bed filled with cenospheres (solid hollow permeable spherical particles). The permeability of cenosphere walls and the drag coefficient of cenospheres in the gas flow are determined.

Microstructure and Properties of 20Cr23Ni18 (AISI 304L) Thin Steel Tapes Obtained by Melt Spinning

“…The economic efficiency of implementation of methods for direct production of cast tape and tape directly from the melt is obvious, associated with a sharp decrease in investment costs and significant energy savings, compared to traditional rolling methods, etc. In open sources there is a number of works devoted to the study of high-performance installations for continuous casting of thin tapes with a microcrystalline structure using two crystallizer rolls and development of a method for calculating the optimal parameters of such installations for obtaining tapes of a certain shape with a minimum risk of breaking and tightening the tapes under tension [7][8][9][10]. The majority of the works aimed at studying the processes of spinning in installations with one roll-crystallizer is devoted to the production of tapes of amorphous metal alloys [11,12].…”

Experience in plasma production of hollow ceramic microspheres with required wall thickness

“…Among such processes is the production of lightweight and buoyant materials [1], strong composite sound and heat insulators [2], heat-insulating paint coatings [3], lightweight proppants [4], radio transparent ceramics and electromagnetic interference isolation [5][6][7], explosives [8], catalysts [9], inertial fusion confinement targets [10,11], etc. Investigations into the possibility to extract helium out of natural gas [12] and to store hydrogen [13] using the selective gas permeability of ceramic hollow spheres are under way. In the majority of the new technologies, only the light weight, or low density, of the hollow powders is used.…”