Variable thermal conductivity in micropolar porous thermoelastic layer resting on elastic half-space

Purpose The purpose of this study is to develop and analyze a new boundary value problem for a micropolar porous thermoelastic layer with temperature-dependent thermal conductivity resting on an elastic half space. The work aims to understand how micropolar effects, porosity, and variable thermal conductivity influence thermo mechanical field distributions and wave propagation characteristics. Design/methodology/approach A coupled thermoelastic model incorporating micropolarity, porosity, and nonlinear temperature dependent thermal conductivity is formulated. The nonlinearity arising from variable conductivity is linearized using the Kirchhoff transformation. Normal mode analysis is applied to obtain exact analytical expressions for displacement, stress, microrotation, porosity, and temperature fields. Numerical simulations are performed to compare responses corresponding to constant and variable thermal conductivity, and to quantify the influence of micropolar and porous parameters. Findings Results show that variable thermal conductivity significantly reduces the magnitudes of thermo mechanical field variables, producing smoother and more realistic profiles. Porosity strongly affects wave behavior, modifying displacement and stress distributions and inducing oscillatory characteristics. The combined effects of voids and thermal variability enhance damping and stabilize thermal responses within the micropolar porous medium. Originality/value This work presents the first analytical model integrating micropolarity, porosity, and variable thermal conductivity in a thermoelastic layer bonded to an elastic half space. The findings provide valuable insights for the design of thermally loaded layered systems such as thermal barrier coatings, aerospace components, porous composites, and geomechanical structures.