Creep-damage modelling for micro gas turbine combustion chambers lifetime prediction

Micro Gas Turbines (MGTs) are nowadays largely used for electrical and thermal energy production in small buildings households. Their reliability compactness allow them to operate thousands of hours with minimal maintenance. However, the long exposure at high temperatures combustion chambers can promote creep, which induce fatigue potential failure these components. Creep-induced damage MGTs has not yet been thoroughly investigated, due lack numerical tools able model strongly coupled phenomena. This study presents development a Fortran-based subroutine integrated into ANSYS APDL. The code allows life assessment based on Lemaitre-Chaboche creep model. Secondary stress relaxation modeled high-temperature resistant alloy Inconel718. A new set temperature-dependent parameters Norton equation is provided, method obtain from rupture tests outlined. validated shows good agreement experimental data. correctly reproduces visco-plasticity, under typical operating temperatures. constitutes foundation life-assessment analysis chambers. results highlight impact temperature component’s importance integrating preliminary design