Investigation of the Thermal Stressed State of a Reactor for Producing Hydrogen from Methane
I. V. Kudinov, A. A. Pimenov, G. V. Mikheeva
Samara State Technical University, Samara, 443001, Russia
Keywords: methane pyrolysis, two-layer cylinder, boundary-value problems, thermal conductivity, thermoelasticity, integral method of thermal balance
Abstract
This paper presents a study of the thermal and thermally stressed state of a reactor in the form of a quartz cylinder filled with tin for producing hydrogen by methane pyrolysis. When determining the temperature state, the problem for the two-layer structure (quartz-tin) using the Heaviside function was reduced to the problem for a single-layer structure with variable (piecewise homogeneous) properties of the material. An analytical solution including algebraic polynomial functions with coefficients exponentially stabilizing in time was obtained by determining the position of the temperature disturbance front and additional boundary conditions using the integral method of heat balance. Using the obtained solution, quasi-static temperature stresses were determined in the case where the structure is a two-layer hollow cylinder (flat deformation). The layer conjugation method was used to obtain an exact analytical solution of the thermoelasticity problem, from which it follows that at the point of contact of the layers, the hoop and axial stresses have a jump (discontinuity) with a change of sign in it. It is found that in certain start-up modes, the hoop and axial stresses can exceed the tensile strength of the quartz layer. The results were used to determine start-up modes in which the stresses do not exceed permissible values.
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