Analysis of Gas-Fired Ceramic Radiant Tubes During Transient Heating: Part II—Thermoelastic Stress Analysis

Abstract

Abstract Transient radial and axial temperature distributions based on measured external surface temperatures and finite-element calculations were used with temperature dependent elastic material properties to determine the thermoelastic stresses experienced by reaction-bonded and sintered-alpha silicon-carbide open ended radiant tubes during gas-combustion beating. The resulting stresses exhibited a dependence on the radial temperature difference and the curvature of the axial temperature distribution. A failure rate analysis using a two-parameter Weibull formulation with a polyaxial stress approximation, the calculated surface and volume principal stresses, and temperature-dependent surface and volume Weibull strength data indicated low failure rates and the viability of both materials for the transient heating conditions studied.