Some results in viscoelasticity theory via a simple perturbation argument
Some results on the well-posedness of an integro-differential Frémond model for shape memory alloys.
Sottopotenziali energia libera per l'isteresi meccanica
This paper deals with free-energy lower-potentials for some rate-independent one-dimensional models of isothermal finite elastoplasticity proposed in [1]. Extending the thermodynamic arguments of Coleman and Owen [3] to large deformations, the existence, non-uniqueness and regularity of free-energy as function of state are deduced rather than assumed. This approach, along with some optimal control techniques, enables us to construct maximum and minimum free-energy functions and a wide class of differentiable...
Spectral perturbations in linear viscoelasticity of the Boltzmann type
Stability properties of a class of viscoelastic beams of the hereditary type
The paper deals with the problem of equilibrium stability of prismatic, homogeneous, intrinsically isotropic, viscoelastic beams subjected to the action of constant compressive axial force in the light of Lyapounov's stability theory. For a class of functional expressions of creeping kernels characteristic of no-aging viscoelastic materials of the hereditary type, solution of the governing integro-differential equations is given. Referring to polymeric materials of the PMMA type, numerical results...
Su alcune classi di potenziali termodinamici come conseguenza dell'esistenza di particolari onde di discontinuità nella meccanica dei continui con deformazioni finite
Sul teorema di Liouville per deformazioni conformi
Sulla nozione di stato per materiali viscoelastici di tipo «rate»
Si considera un materiale viscoelastico lineare in cui la funzione di rilassamento è la somma di esponenziali. Lo stato di questi sistemi non è necessariamente assegnato dalla storia passata di , ma è sufficiente fornire il valore iniziale del tensore di deformazione , del tensore degli sforzi e delle sue derivate. Infine per questi materiali abbiamo ottenuto una espressione dell'energia libera come una funzione dello stato di dimensione finita .
Sull'espressione analitica di alcune grandezze termodinamiche nei materiali con memoria
Sull'invertibilità dell'equazione costitutiva della viscoelasticità lineare
Viene affrontato lo studio della inversione dell'equazione costitutiva (1.2) della viscoelasticità lineare, in funzione dei diversi spazi topologici su cui si può definire tale problema. In particolare si mostra che l'inversione di (1.2) ammette risposte completamente diverse al variare degli spazi di definizione, anche quando tali spazi vengono scelti sulla base delle topologie legate alle funzioni energia del problema considerato.
Sur les équations du type ψ(x,h)=0 (I)
The dynamics of a tied body against an obstacle
Thermo-viscoelastic Rayleigh waves under the influence of couple-stress and gravity.
Thick obstacle problems with dynamic adhesive contact
In this work, we consider dynamic frictionless contact with adhesion between a viscoelastic body of the Kelvin-Voigt type and a stationary rigid obstacle, based on the Signorini's contact conditions. Including the adhesion processes modeled by the bonding field, a new version of energy function is defined. We use the energy function to derive a new form of energy balance which is supported by numerical results. Employing the time-discretization, we establish a numerical formulation and investigate...
Time-Fractional Derivatives in Relaxation Processes: A Tutorial Survey
2000 Mathematics Subject Classification: 26A33, 33E12, 33C60, 44A10, 45K05, 74D05,The aim of this tutorial survey is to revisit the basic theory of relaxation processes governed by linear differential equations of fractional order. The fractional derivatives are intended both in the Rieamann-Liouville sense and in the Caputo sense. After giving a necessary outline of the classica theory of linear viscoelasticity, we contrast these two types of fractiona derivatives in their ability to take into...
Two shallow-water type models for viscoelastic flows from kinetic theory for polymers solutions
In this work, depending on the relation between the Deborah, the Reynolds and the aspect ratio numbers, we formally derived shallow-water type systems starting from a micro-macro description for non-Newtonian fluids in a thin domain governed by an elastic dumbbell type model with a slip boundary condition at the bottom. The result has been announced by the authors in [G. Narbona-Reina, D. Bresch, Numer. Math. and Advanced Appl. Springer Verlag (2010)] and in the present paper, we provide a self-contained...
Un teorema di unicità in viscoelasticità lineare
Unilateral dynamic contact of von Kármán plates with singular memory
The solvability of the contact problem is proved provided the plate is simply supported. The singular memory material is assumed. This makes it possible to get a priori estimates important for the strong convergence of gradients of velocities of solutions to the penalized problem.
Viscoelastic frictionsless contact problems with adhesion.
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