Hotspot formation driven by temperature-dependent coefficients in one-dimensional thermoviscoelasticity
Michael Winkler
TL;DR
The paper analyzes a one-dimensional thermoviscoelastic model with temperature-dependent viscosity and stiffness, introducing $\gamma(\Theta)$ and $a\gamma(\Theta)$. It develops a local solvability framework and a refined extensibility criterion showing that finite-time blow-up in the solution obliges $\Theta$ to become unbounded, i.e., hotspot formation. By transforming to $v=u_t+au$ and employing a Moser-type iteration, it derives $L^{\infty}$ bounds and gradient controls that underpin the blow-up analysis. The main results establish finite-time blow-up under superlinear growth of $\gamma$ through two mechanisms: large initial energy and large initial temperature, providing precise thresholds and highlighting hotspot formation as a fundamental feature of temperature-dependent thermoviscoelastic systems with Kelvin-Voigt-type damping.
Abstract
This manuscript is concerned with a two-component evolution system generalizing the classical model for one-dimensional thermoviscoelastic dynamics in Kelvin-Voigt materials in the presence of temperature-dependent viscosities and elastic stiffnesses. Under suitable assumptions on the growth of these ingredients and on the initial data, the occurrence of finite-time blow-up with respect to the $L^\infty$ norm in the temperature variable is discovered.
