The mechanical behavior of 3D multi-layered braided composite tubes was analyzed using a multi-scale modelling approach. Considering the braiding parameters and the fiber volume fraction of the composite tubes, firstly a unit-cell of the composites was determined based on the motion of yarn carriers and modeled using TEXGEN software. The unit-cell was imported into finite element software to ca...

The Polish ventricular assist device, POLVAD_EXT, is made of a polymer designed to be covered with a nanocoating of titanium nitride to improve haemocompatibility. A loss of cohesion can occur between the coating and the substrate. An analysis of stress and strain states in a multi-scale model of the blood chamber was performed in the finite element computer program, VADFEM. The multiscale mode...

In this paper, a multiscale approach to capture the behaviour of material layers that possess a micromorphic mesostructure is presented. To this end, we seek to obtain a macroscopic traction-separation law based on the underlying meso and microstructure. At the macro level, a cohesive interface description is used, whereas the underlying mesostructure is resolved as a micromorphic representativ...

Numerical methods for parabolic homogenization problems combining finite element methods (FEMs) in space with Runge-Kutta methods in time are proposed. The space discretization is based on the coupling of macro and micro finite element methods following the framework of the Heterogeneous Multiscale Method (HMM). We present a fully-discrete analysis in both space and time. Our analysis relies on...

Abstract. This work establishes a formal derivation of local projection stabilized methods as a result of an enriched Petrov-Galerkin strategy for the Stokes problem. Both velocity and pressure finite element spaces are enhanced with solutions of residual-based local problems, and then the static condensation procedure is applied to derive new methods. The approach keeps degrees of freedom unch...

This paper presents a multi-scale model in phase transitions of solid materials with both macro and micro effects. This model is governed by a semi-linear nonconvex partial differential equation which can be converted into a coupled quadratic mixed variational problem by the canonical dual transformation method. The extremality conditions of this variational problem are controlled by a triality...

The expressiveness of the C/C++ preprocessing facility enables the development of highly configurable source code. However, the usage of language constructs like macros also bears the potential of resulting in highly incomprehensible and unmaintainable code, which is due to the flexibility and the “cryptic” nature of the preprocessor language. This could be overcome if suitable analysis tools w...

Micro- and macro-element contents of several commercial fruit juices purchased from marked were determined by inductively coupled plasma atomic emission spectroscopy. Among the minor elements determined, Zn, Cu, Mn, Mo, Co, Cd and Ni were found to be lover. Major mineral contents of fruit juices were established as Ca, K, Mg and P. The potassium contents of fruit juices were determined at the h...

The paper presents the results of computer modeling and prediction mechanical properties composite materials with a polycarbonate matrix filled short glass inclusions. At micro-level, influence volume inclusions on designed based is studied in DIGIMAT (France) program. It was found that ratio sizes range 468÷60, particles have needle shape, material such has higher stress limit elastic modulus ...

This paper presents the development of a Representative Volume Element (RVE) for Ultra-high-Molecular-Weight-Polyethylene (UHMWPE) composites. The numerical models were based on fibrillar nature UHMWPE fibres, which consist smaller scale, continuous through-the-length macro-fibrils. A three-dimensional constitutive model macro-fibrils was developed and implemented in LS-DYNA explicit finite ele...