SIMULIA Ressourcen-Center

This paper presents an FEA approach by using a damaged plasticity model to capture the complex thermal and mechanical behavior of cement material. The damaged plasticity model considers the thermal conductivity, tri-axial stress effect, strain-hardening due to plasticity, strain-softening due to cracking and cyclic loading responses. This paper also presents a post-cracking design concept as a new design basis to allow limited cement cracking, providing that the permeability of the cement remains within an acceptable limit. An illustrative example is presented to demonstrate the use of FEA approach and post-cracking design concept for the design of thermal well cements.

Customer Papers

Composite products are gaining wide popularity in industrial production. But after getting impact damage composite parts do not behave as metals due to absence of plasticity. It is very important to analyze BVID damage and residual strength of the composite structure after impact damage. The analysis was carried out on the damage after low velocity impact with use of Virtual Crack Closure Technique and Hashin criteria with corresponding degradation model. For detailed representation of stress fields submodeling technique was used as well.

Customer Papers

In the Fracture Mechanics field, standard industrial methods for crack growth analysis are mainly based on analytic calculations as classical Finite Element approaches are not practical to deal with discontinuities such as fatigue cracks due to the associated high computational costs. eXtended Finite Element Method (XFEM) is one of the methodologies that are being developed in the recent years in order to overcome the limitations associated to classical approaches, especially for complex analysis. However limited industrial experience is available to adopt this methodology as a standard practice in the aircraft industry.

Customer Papers

Finite Element Simulation of Friction Stir Welding (FSW) is a problem involving large deformations and is often difficult to solve using the classical Finite Element Method (FEM). Large mesh distortions and contact problems can occur due to the large deformations such that a convergent solution cannot be achieved. Since in ABAQUS, a Coupled Eulerian Lagrangian (CEL) approach has been developed to overcome the difficulties with regard to FEM and large deformation analyses. In this article, this method is investigated regarding its capabilities in simulating FSW process.

Customer Papers

Various elastoplastic constitutive models have been proposed to predict the structural stiffness; most of them use an associated flow rule, which defines a plastic flow direction normal to the yield surface. These models, based on this assumption, have contributed to the predictions of elastoplastic deformations of solid structures in several applications, however, in some cases, they tend to overestimate the structural stiffness. In order to overcome this defect, we have adopted an unconventional elastoplastic model capable of taking into account the generation of the inelastic strain rate not only along the direction normal to the yield surface but also along the tangential one. In this paper the aforementioned model has been studied by applying a series of non-proportional loading paths to a thin wall pier and comparing the results obtained with the ones derived by neglecting the tangential contribution.

Customer Papers

A spreading environmental awareness has prompted a global movement towards leadfree electronic products, in which lead-free tin plating is included. Lead-free tin plating provides good solderability equal to tin-lead plating, however the spontaneous whisker growth on lead-free tin plating is a serious reliability issue. It's imperative to clarify the whisker generation and growth mechanism. So we have developed a multi-scale simulation technique for calculating tin atom diffusion caused by stress gradient induced by temperature change and crystal orientation distribution in polycrystalline tin plating. This multi-scale simulation technique uses molecular dynamics (MD) simulation and a finite element analysis (FEA).

Customer Papers

The presentation is about the application and impact of Abaqus and iSight simulations for corrugated board and packaging within Smurfit Kappa. Abaqus and Isightare used for the development of the prediction formulas, used in our prediction tool PaperToBox. PaperToBox is considered as industry leading. This tool is internally used by 1800 colleagues, resulting in >500 000 calculations per year. Also this tool provides the target values for the newly rolled-out quality measurement system, the “Board Referee”.

Customer Papers

Today, numerous aeroelastic structures are deployed over a finite time period, such as flaps, spoilers, control surfaces, and wheel bay and bomb bay doors. These devices must be both divergence and flutter free. Current state-of-art simulations verify this by applying a quasi-steady assumption that does not require the system to physically deploy within the computations. That is, the structure is assumed elastic but does not possess the “large” motion associated with the device’s path of travel. While these simulations have strong technical merit, especially in the case where a structure is inadvertently locked in a partially deployed position, they are unable to capture all of the relevant physics.

Customer Papers

Composite materials based on thermoplastic matrix became a popular choice as a material for modern structures. Nevertheless, the manufacturing process of this type of materials have many technology parameters, which have to be determined before the first composite part is produced. The study of influence of all parameters on final quality of composite part by means of technological experiments are time and cost consuming. This makes engineers to study the way of the modeling of thermoplastic composite forming process. This research is dedicated to the modeling of thermoplastic material under different conditions.

Customer Papers

Fokker Landing Gear has a history in development of composite technology for landing gear applications. In order to successfully design and qualify composite landing gear parts it is essential to be able to reliably predict the mechanical and failure behavior of the composite material. Therefore the goal of this study was to develop, calibrate and validate a material model which can be used to reliably predict the failure behavior of fiber-reinforced composites. In the developed material model the fibers and resin are modelled as separate materials with their own specific material and failure behavior. The interaction between the fibers and resin is accounted for using a (proprietary) modified Mori-Tanaka approach.

Customer Papers

The latest generation of rotary steerable drilling systems make it possible to reach hydrocarbons located deeper and in more hostile environments than ever before. These systems give the directional driller, standing some 10,000ft above on the rig floor, the ability to steer the well path in real-time to reach the elusive ‘pay zone’. Rotary steerable drilling systems, which are located at the end of the drilling assemblies, are exposed to extreme conditions. In addition to temperatures in excess of 390°F and pressures up to 25,000 psi, they must also convey compressive and bending loads, torque and rotation to the drill bit from the surface, all while controlling the 3D trajectory of the wellbore.

Customer Papers

In the oil and gas industry, steam assisted gravity drainage (SAGD) is an operation where steam is injected into a reservoir to lower the viscosity of heavy oil to allow its production. The injection of steam leads to thermally induced stresses and pore pressure changes in the reservoir and its proximity. Although the pressure and temperature evolution can be modelled with reservoir simulators, they neglect the change of the stress field in relation to these properties, which can impact the stability of faults and fractures. These active faults and fractures, in turn, affect the fluid transport properties. In order to assess the potential for fault and fracture (re-)activation we created a model of a SAGD operation by coupling the outcome of a reservoir simulation to a 4D geomechanical finite-element model using Abaqus.

Customer Papers