Luis Rodríguez-Tembleque

Quasistatic Electro-Elastic Contact Modeling Using the Boundary Element Method

A three-dimensional boundary element methodology to study frictionless indentation response of piezoelectric (PE) materials is presented. The boundary element method (BEM) is used in order to compute the electro-elastic influence coeffcients of fully anisotropic piezoelectric solids. The proposed contact formulation is based on the augmented Lagrangian method presented in [33, 34, 35] and makes it possible to consider piezoelectric materials under different mechanical and electrical boundary conditions (i.e. insulating indenter and conducting indenter). The methodology is validated by comparison with theoretical solutions presented in the literature.

Crack Surface Frictional Contact Modelling in Piezoelectric Materials

Piezoelectric materials exhibit an electromechanical coupling which allows for their use assensors or energy harvesting devices (direct piezoelectric effect) or actuators and shape control de-vices (inverse piezoelectric effect). They are applied in many technological sectors of current interestsuch as the aerospace and automotive industries, and they are generally constructed in block form orin a thin laminated composite. The study of the integrity of such materials in their various forms andsmall sizes is still a challenge nowadays. To gain a better understanding of these systems, this workpresents a crack surface contact formulation which makes it possible to study the integrity of theseadvanced materials under more realistic crack surface multifield operational conditions. The formu-lation uses the BEM for computing the elastic influence coefficients and contact operators over theaugmented Lagrangian to enforce contact constraints on the crack surface, in the presence of electricfields. The capabilities of this methodology are illustrated solving a benchmark problem.

A Dual BEM Formulation for Thermo-Magneto-Piezo-Electric 2D Fracture Problems

A hypersingular approach of the boundary element formulation -BEM- is presented for the analysis of the temperature in fracture problems of multifield materials. A fundamental solution based on the extended Stroh formalism is considered. Hypersingular integrals arising in the traction boundary and heat flux integral equations are computed through a regularization technique causing that only regular integrals are computed numerically. The generality of the method allows the study of 2D solids with no shape restrictions. Generalized intensity factors -IFs- are accurately computed from nodal values next to crack tip. Finally, the possibilities of the presented approach are discussed in order to apply it for the assessment of the influence of temperature in fracture problems for materialspresenting mechanical, magnetic and/or electrical coupling

Boundary element analysis of the frictionless indentation of piezoelectric films

The boundary element method is used for studying frictionless indentation response of piezoelectric (PE) films under spherical indenter (i.e. sphere) and circular cylindrical indenter (i.e. punch). An augmented Lagrangian formulation is employed to solve PE films of finite thickness under contact conditions. The methodology is validated by comparison with theoretical solutions presented in the literature for the two limiting cases: infinitely thick and infinitely thin PE films closed-form solutions. Furthermore, the formulation is applied to compute the indentation response of those cases in between.