Optimal scalar products in the Moore-Gibson-Thompson equation

We study the third order in time linear dissipative wave equation known as the Moore-Gibson-Thompson equation, that appears as the linearization of a the Jordan-Moore-Gibson-Thompson equation, an important model in nonlinear acoustics. The same equation also arises in viscoelasticity theory, as a mo...

Descripción completa

Detalles Bibliográficos
Autores: Pellicer, Marta, Solà-Morales Rubió, Joan de|||0000-0003-2896-2917
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/130655
Acceso en línea:https://hdl.handle.net/2117/130655
https://dx.doi.org/10.3934/eect.2019011
Access Level:acceso abierto
Palabra clave:Differential equations, Partial
Moore-Gibson-Thompson equation
standard linear viscoelastic model
normal operator
optimal exponential decay.
Equacions diferencials parcials
Classificació AMS::35 Partial differential equations
Classificació AMS::47 Operator theory::47D Groups and semigroups of linear operators, their generalizations and applications
Àrees temàtiques de la UPC::Matemàtiques i estadística
Descripción
Sumario:We study the third order in time linear dissipative wave equation known as the Moore-Gibson-Thompson equation, that appears as the linearization of a the Jordan-Moore-Gibson-Thompson equation, an important model in nonlinear acoustics. The same equation also arises in viscoelasticity theory, as a model which is considered more realistic than the usual Kelvin-Voigt one for the linear deformations of a viscoelastic solid. In this context, it is known as the Standard Linear Viscoelastic model. We complete the description in [13] of the spectrum of the generator of the corresponding group of operators and show that, apart from some exceptional values of the parameters, this generator can be made to be a normal operator with a new scalar product, with a complete set of orthogonal eigenfunctions. Using this property we also obtain optimal exponential decay estimates for the solutions as t¿8, whether the operator is normal or not.