Abstract Durability and reliability have been studied for decades through intensive trial-error experimentation. However, there are numerous fields of application where the costs associated with this approach not acceptable. In lubricated machines severe dynamic loads, such as high-power-density engines, simulation tools offer clear advantages over testing. Prototypes multiple scenarios can be cost-effectively simulated to assess different lubricants engine configurations. The work presented...

This paper studies the stress state of a threaded fastening by using Finite Element (FE) models, applied to surgical screws in cortical bone. There is general interest studying states induced different elements joint caused thread contact. Analytical models were an initial approach, and later FE allowed detailed complex phenomena related these joints. Different have evaluated standard joints machinery structures, being symmetric. However, employ asymmetric geometry, selected improve level...

High-performance engines are highly optimized machines; therefore, any identification of potential improvement requires a detailed study to assess different performance scenarios, working fluids and engine configurations. Simulation tools among the best ways all possible options. In this framework, validated elastohydrodynamic (EHD) simulation model connecting rod journal bearing is used lubricant formulations in mixed lubrication scenarios. To simulate realistic scenario, finite element...

In this paper, we characterized the hyperelastic and damage behavior of Extensor Digitorum Longus (EDL) human tendon under loading conditions. The study was conducted in both categories models, phenomenological physically motivated, to allow prediction macroscopic response specific conditions, assuming that its follows a anisotropic model conjunction with law. We benchmarked multiple models fit tendons uniaxial tensile by employing genetic algorithm, obtained material parameters for elastic...

In this study, we have been working within the framework of mathematical characterization materials with complex behavior, and used as input data for simulations in finite elements codes. We researched behavior hyperelastic viscoelastic qualities. There are models type materials; however, they lean on parameters that to be previously determined each material, only then, their calculation can estimate an answer material under specific loading conditions. focused applying Prony series...

It is not uncommon to use profiles act as energy absorption parts in vehicle safety systems. This work analyses an impact attenuator based on a simple design and discusses the of thermoplastic material. We present mechanical test for prototype. develop simulation model using finite element method explicit dynamics, we evaluate most appropriate mesh size integration describing results. Finally, consider performance different materials, metallic ones (steel AISI 4310, Aluminium 5083-O) foam...

Current knowledge of the behavior heavy quadricycles under impact is still very poor. One most significant causes lack energy absorption in vehicle frame or its steel chassis structure. For this reason, special steels (with yield stresses equal to greater than 350 MPa) are commonly used automotive industry due their great strain hardening properties along plastic zone, which allows good impact. This paper presents a proposal for quadricycle system meets percentages conventional vehicles...

Bone tissue is a material with complex structure and mechanical properties. Diseases or even normal repetitive loads may cause microfractures to appear in the bone structure, leading deterioration of its A better understanding this phenomenon will lead predictions fracture bone-implant performance. In work, model proposed by Frémond Nedjar 1996 (initially for concrete structures) numerically analyzed compared against specific García et al. 2009. The objective evaluate both models implemented...

Passive safety systems of cars include parts on the structure that, in event an impact, can absorb a large amount kinetic energy by deforming and crushing design-controlled way. One such absorber part, located front Formula Student car, was measured under impact test bench. The is modeled within Finite Element (FE) framework including weld characteristics failure description. continuous welding feature almost always disregarded included models. In this work, FE model fully defined to...

In this paper, we present the optimization of a vibration mitigation system for railway bridges. These structures are subjected to significant moving loads, whose dynamic characteristics may produce resonance effects, compromising integrity bridge and security passengers if speed or load train is not controlled. The study focuses on Auxiliary Beam system. It consists beam located under connected slab by viscous dampers. symmetry problem allowed use 2D Finite Element model This was used...

Transcatheter Aortic Valve Implantation (TAVI) or Replacement (TAVR) is a promising treatment for aortic valve stenosis, consisting of procedure to replace damaged native by bioprosthetic one. This replacement control the flow blood using leaflets that are similar ones valve. Commonly manufactured bovine porcine pericardium, it tissue histologically composed collagen fibers embedded into nearly-isotropic matrix, where their distribution makes pericardium behave as an anisotropic hyperelastic...

In this work, we numerically study a thermo-mechanical problem arising in poro-viscoelasticity with the type III thermal law. The thermomechanical model leads to linear system of three coupled hyperbolic partial differential equations, and its weak formulation as parabolic variational equations. Then, using finite element method implicit Euler scheme, for spatial approximation discretization time derivatives, respectively, fully discrete algorithm is introduced. A priori error estimates are...

In this paper, we numerically study a dynamic viscoelastic problem. The variational formulation is written as linear parabolic equation for the velocity field. An existence and uniqueness result recalled. Then, fully discrete approximations are introduced using implicit Euler scheme finite element method, which some priori error estimates derived, leading to convergence of algorithm under suitable additional regularity conditions. Finally, one- three-dimensional numerical simulations...

In this paper, the reliability of a finite element (FE) model including carbon-fibre reinforced plastics (CFRPs) is evaluated for case complex thin-wall honeycomb structure designed scientific instrument, such as calorimeter. Mechanical calculations were performed using FE models CFRPs, which required specific definition to describe micro-mechanical behaviour orthotropic materials coupled homogeneous ones. There are well-known commercial software packages used powerful tools analyzing...

En este trabajo se presenta una metodología para el estudio mediante simulación numérica de la capacidad adaptación estructura soporte (stent) las prótesis valvulares aórticas empleadas en procedimiento implantación valvular aórtica transcatéter (TAVI) a anatomía particular un paciente concreto. El TAVI es práctica habitual pacientes con enfermedades degenerativas válvula aórtica, como estenosis valvular, que no pueden ser intervenidos métodos convencionales sustitución por elevado riesgo...

Viscoelastic materials play a key role in mechanical designs due to its numerous application. Even though numerical models already exist and are included commercial codes, the precision of calculation depends strongly on material characterization parameters identification. In our research, we propose viscoelasticity material, whose nonlinear elasticity was previously defined with strain–stress test, then perform relaxation test. Also three rheological studied order fit this The optimization...

In this paper, we deal with the numerical approximation of some porous-thermoelastic problems. Since inertial effects are assumed to be negligible, resulting motion equations quasistatic. Then, by using finite element method and implicit Euler scheme, a fully discrete is introduced. We prove stability property main error estimates result, from which conclude linear convergence under appropriate regularity conditions on continuous solution. Finally, several simulations shown demonstrate...