@article{Chen2026, 
author = {Xuejiao Chen and Zijun Cheng},
title = {Spatial decay estimate for the MGT-Fourier model on a semi-infinite cylinder in              R        2},
year = {2026},
journal = {Electronic Research Archive},
volume = {34},
number = {6},
pages = {3696-3712},
keywords = {Saint-Venant principle, MGT-Fourier model, integral-differential inequality, semi-infinite cylinder},
url = {https://www.sciopen.com/article/10.3934/era.2026167},
doi = {10.3934/era.2026167},
abstract = {This study investigates the spatial decay estimate for a coupled Moore-Gibson-Thompson (MGT)-Fourier system on a semi-infinite cylinder in              R        2  . The system is comprised of a third-order MGT displacement equation and a parabolic heat equation with symmetric coupling. Using a weighted energy functional and an integral-differential inequality, we establish the exponential decay along the axial direction. This result offers a generalized Saint-Venant principle for coupled dissipative thermoviscoelastic models, thus extending the classical analysis to higher-order systems and advancing our understanding of MGT equations in an unbounded domain.}
}