SIMULIA Ressourcen-Center

The objective of this paper is to introduce an economical and user-friendly technique for estimating a specific type of finite element simulation uncertainties, or, "error bars," for a class of mathematical models, of which no closed-form or approximate solution is known to exist. Using Python, Abaqus-Python, and a public-domain statistical data analysis software package named Dataplot, we present a design-of-experiments-based Python-Dataplot-Uncertainty Plug-In (PD-UP) to estimate the finite element simulation uncertainties in a mathematical model due to variability in modeling parameters such as material property constants, geometric parameters, loading rates, etc.

Customer Papers

Perforated base pipe is an important component in a completion system. Field applications dictate that a good perforated base-pipe design should have good expandability and good post-expansion tensile strength and collapse strength. High fidelity FEA models for evaluation of expandable base pipes have been developed; however, to optimize hole pattern design (size, shape, placement pattern) of a given size base pipe, even numerically, can be expensive and time consuming. Using FEA models and a genetic algorithm-based multi-objective optimization scheme, the authors have successfully optimized a perforated base pipe in a relatively short period of time. The significant improvement over standard design has been demonstrated by physical tests. Several aspects of the optimization process will be presented in this paper.

Customer Papers

At The Timken Company, Abaqus is used in both product and process development. Several examples are presented in this paper. New product applications rely on the linear and nonlinear implicit solvers of Abaqus. New process applications rely on the Abaqus explicit solver. The explicit solver is used to decrease solve time while giving accurate analysis results. The user routine is used to specify stress boundary conditions on the model under Hertzian contact. Finite Element Analysis is an important tool that enables evaluation of product and process design before making prototypes.

Customer Papers

Carbon-fiber-reinforced plastics (CFRP) are being used for highly loaded lightweight structural components for many years. Up to now mostly insufficient two-dimensional classical failure criterions, which are embedded into FE-software like Tsai-Wu, Hill, etc. have been used for the dimensioning of composites. To achieve better predictions of the three-dimensional complex composite failure behavior newer, so-called action-plane based failure criterions have been developed. In addition to this, the complex step-by-step component failure process including post-failure load redistribution can be accurately simulated using a combination of these newer criterions with a convincing material degradation model.

Customer Papers

The paper present results obtained using Abaqus/Explicit software for predicting the impact damage and failure response of various aircraft structures under high velocity impact loadings. Two types of problems are considered. The first concern the crash simulation of a generic airplane fuselage section and the second concern study of bird strike on typical wing leading edge using both metallic and composite structure. In the case of an aircraft fuselage hitting the ground, both vertical crash test and steep glide slope crash conditions are considered. The main objective was then to develop a methodology for performing such fast transient dynamic simulation tests and to determine in each case the residual velocity as well the various deformation modes associated with particular loading and crash conditions.

Customer Papers

Each year companies spend millions of dollars for developing new products with high quality and reliability. Highly reliable products require longer test times to verify, and usually takes a few iteration of design-test-fix cycle. Development time can be minimized by (1) doing accelerated testing (ALT) and (2) reducing the design-test-fix cycle by developing methods to predict and test for reliability in simulation environment. Finite element modeling and analysis provides an excellent alternative in evaluating designs to improve on reliability. In this paper, a probabilistic simulation methodology is proposed using a combination of simulation modeling and statistical techniques to predict and improve the drop reliability of a product under repeated random loading.

Customer Papers

Dynamic excitation due to a pipe break can cause pipe to abruptly displace and hit the components, instrumentation and equipment nearby. In order to minimize the extensive damage caused by such pipe whips, different types of restraints and supports are designed for the pipelines. Here, structural dynamic behaviour of pipelines is studied with finite element method. A relatively short pipe line section with one bend and one restraint and rigidly fixed from its other end is chosen as a test case. The usability of different types of elements provided by Abaqus code in modelling the pipe, restraint and adjacent civil structure is tested.

Customer Papers

Over the past couple of decades, standard test methods and material models have existed for rubber-like materials. These materials were classified under the category of Hyperelastic materials. Well established physical test methods and computational procedures exist for the characterization of the material behavior in tension, compression, shear volumetric response, tear strength etc. In this paper, we make an attempt to demonstrate the use of such standard test methods and the applicability of such test data for performing finite element analyses of complex nonlinear problems using Abaqus. Our goal is to demonstrate the effective use of standard physical test data to model multi-axial loading situations and fracture of hyperelastic materials through tear tests and indentation test simulations.

Customer Papers

A simulation is needed to investigate the heat generation on a rubber section of a wheel which is running at a constant speed. In parallel with this loading case a rig test was carried out to verify the finite element analysis. For analysis point of view a traditional way is to use the Lagrangian approach in which the mesh is used to discretize the structure (both materials and mesh are spatially fixed) and many revolutions are typically required to obtain the state of interest to the analyst, this approach is prohibitively expensive and cumbersome. Abaqus provides an approach based on the Eulerian theory in which the finite element mesh of the wheel does not rotate, instead the materials flow through the mesh.

Customer Papers

Nonlinear analysis using Riks method is suitable for predicting buckling, post-buckling, or collapse of certain types of structures, materials, or loading conditions, where linear or eigenvalue method will become inadequate or incapable, especially when nonlinear material, such as plasticity, is present, or post-buckling behavior is of interest. These structures usually undergo finite deformations due to complicated loadings or material plasticity before buckling actually occurs, which changes system matrices, and thus, makes the eigenvalue analysis inaccurate, difficult, or even impossible to perform. This study intends to demonstrate the use of Riks method in the nonlinear analysis of buckling and post-buckling behaviors of a flexible structure under bending and compressive loads.

Customer Papers

Transient dynamic simulations gain importance in the automotive industry and modern fatigue postprocessors are apt to evaluate the fatigue damage. However, additional insight into a structure’s behaviour may be obtained from observing the displacements. Displacement patterns are important for design engineers in order to improve the structure. With proportional static loads it is trivial to display and understand the displacements, but the displacements in dynamic simulations are often very complicated. This paper describes a novel method for visualising the transient displacements of mode-based analyses. Based on the modal displacements a new simple, yet fatigue equivalent, modal displacement is computed and visualized instead.

Customer Papers