Thermal-Stress Analysis: Theory and Practices
Thermal-Stress and Thermal-Deflection analyses are an important subset of general finite element analysis (FEA) modeling. Such analyses are common in the development of rocket motors, ASME pressure vessels, electronics (PCB), electronic systems (automotive lamp systems), composite curing mandrels, generators, satellites and etc.
This technical white paper is part of a technical seminar that was presented in 2015 for our sister company AppliedCAx. This white paper presents the basic principles of linear, thermal-stress and thermal-deflection analysis. We say “linear” since it is starting point if one endeavors to move forward with more complex type of analyses. For this seminar we will use thermal-stress to cover any type of mechanical behavior, stress or deflection introduced by a fixed temperature rise (delta) or an induced temperature gradient. The resulting strain from this temperature load is based on the material’s coefficient of thermal expansion (CTE). The development of stress or deflection within the structure due to this fixed strain and/or variable strain is dependent upon many factors that will be discussed with easy-to-follow basic examples.
With this background, the creation of temperature loads is covered using simple boundary conditions or running a steady-state conduction analysis to map out an imposed temperature gradient. These thermal results will then be converted to a temperature load for the thermal-stress or –deflection analyses.
This white paper closes with several examples of thermal-stress work that we have done at Predictive Engineering under our FEA consulting services group.