The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In engineering practice generally empirical durability concepts, such as the Local Strain Approach (LSA) [1], are used for the fatigue life estimation of components. The LSA calculation is based on a given series of reversal points of the elastic stress history, e.g. computed in terms of a finite element model of the component. The fatigue life of components is subject to various factors. During the...
Recently, the problem of modelling fatigue fracture has been approached by the phase‐field method. The approach of Seiler et al. [1] focusses on a reduction of computational cost by combing the phase‐field method for fracture with a classic fatigue concept. For this model, we perform a parameter study analysing the influence of the fatigue degradation function and the crack propagation behaviour under...
In this contribution, particle‐matrix interactions in magneto‐active elastomers are analyzed with regard to the resulting mechanical deformations. By comparing experimental observations with the results of finite element simulations, a fully coupled continuum model for magneto‐active elastomers is validated with the help of real data. The model under consideration permits the investigation of magneto‐active...
In this contribution, the interface region of a fiber reinforced polymer and a metal component is considered within a representative volume element. The connecting surface exhibits a random height distribution with a defined roughness. Under shear loading, different failure mechanisms are studied with respect to the local interface roughness. Furthermore, adhesive failure of the interface and cohesive...
In this contribution, we apply adaptive isogeometric analysis to a phase‐field model for topology optimization. To increase the efficiency of the computation, we perform local mesh refinement and coarsening between the time increments of the simulation. To provide a trial solution for the iterative solver of the next increment, state variables are projected from the old to the new mesh. The quality...
When it comes to failure of a heterogeneous material, the adhesive interfaces linking the different constituents can crucially influence its mechanical behavior. In this contribution, a diffuse description of interfaces in the context of the phase‐field approach to brittle fracture is outlined. Two‐ and three‐dimensional simulations of crack phenomena are presented and serve for validation of the...
Herein, the development and calibration of a macroscopic model for magneto‐active elastomers based on data generated from computational homogenizations is presented. The advantage of this strategy is the possibility to adjust the model independent of any macroscopic sample geometry. Using the calibrated model, the magnetostrictive and magnetorheological effect of macroscopic samples are simulated...
In this contribution, we apply adaptive isogeometric analysis to a phase‐field model for topology optimization. To increase the efficiency of the computation, we perform local mesh refinement and coarsening between the time increments of the simulation. To provide a trial solution for the iterative solver of the next increment, state variables have to be transferred from the old to the new mesh. We...
Remote laser cutting in carbon fibre reinforced polymers is a promising machining technology, which can reduce the main drawback in laser cutting, the heat affected zone. As the heat affected zone has a strong influence on the mechanical behaviour of the composite, an exact characterisation is a key challenge for the simulation and design of fibre reinforced polymers. In order to reach this goal,...
Additively manufactured lattice structures increase the lightweight potential of components for technical applications. When modelling the mechanical behaviour of those lattice structures, imperfections within the structures need to be considered.
In this contribution we investigate the effect of process induced pores of varying size and location inside the lattice structure during pressure tests...
In this contribution, a variational framework for diffuse modeling of cracks in heterogeneous media is analyzed. A static order parameter smoothly bridges the discontinuity at material interfaces, while an evolving phase‐field captures the regularized crack. The key novelty is the combination of a strain energy split with a partial rank‐I relaxation in the vicinity of the diffuse interface. The former...
This papier studies the critical stress state prediction for production‐ and operation‐induced loads on an epoxy‐based mold in an electric rotor. The constitutive behavior of the mold is given by a linear thermo‐viscoelastic material model with an ARRHENIUS‐based time‐temperature superposition, which is modified to also account for chemical curing shrinkage. A finite element analysis (FEA) is performed...
In this contribution, we present a diffuse modeling approach to embed material interfaces into nonconforming meshes with a focus on linear elasticity. For this purpose, a regularized indicator function is employed that describes the distribution of the different materials by a scalar value. The material in the resulting diffuse interface region is redefined in terms of this indicator function and...
Remote laser cutting in carbon fibre reinforce polymers is a promising machining technology which can reduce the main drawback in laser cutting, the heat affected zone. This contribution presents a two‐step modelling approach for the simulation of remote laser cut carbon fibre reinforce polymers, consisting of a damage model for the initially intact material and a model for the thermally damaged material...
Additive manufacturing lifts the restrictions of classical manufacturing methods and enables us to produce lattice structures within otherwise massive bulk material to increase the lightweight potential of technical components. In this contribution we present a multiscale approach to characterise additively manufactured lattice structures. Tensile tests provide the properties of the bulk material...
Multi‐material design aims at the targeted combination of materials with different characteristics in order to meet technical requirements. Especially the combination of metals and fiber‐reinforced plastics (FRP) has led to innovative lightweight structures with high loading capacity and ductility in recent years. The process chain required to produce such structures is characterized by a variety...
Fatigue loads come along with high numbers of load cycles which makes the simulation of fatigue fracture computationally very demanding. We present a numerically efficient method which avoids resolving the loading path and instead requires only one increment per load cycle at most. We combine the phase‐field method for fracture with a classic fatigue concept. A local lifetime variable is obtained,...
Herein, the parametrization of a macro‐model for magneto‐rheological elastomers based on microscopic simulations is presented. Within a computational homogenization, the effective response of the composite system is calculated and the data are used for parameter identification. The merit of this strategy is the adjustment of the model independent of any macroscopic sample geometry. With the developed...
In this contribution, we discuss the modeling of discontinuities using non‐conforming meshes. For weak discontinuities we propose to regularize the sharp material interface over a characteristic length scale. To define the material properties in the transition region, homogenization assumptions are used that fulfill the kinematic compatibility across the interface and the static equilibrium at the...
Fatigue loads and fatigue failure come along with high numbers of load cycles. This makes the simulation of fatigue fracture computationally very demanding, if each load cycle is simulated comprehensively with its loading and unloading phase. We present a numerically efficient method for the simulation of fatigue fracture, which avoids resolving the loading path and instead requires only one increment...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.