Centro de recursos de SIMULIA

Culverts are essential parts of the lock and navigation structures. They transfer water between upper and lower chambers, lakes, rivers and/or ocean side of the navigation system. A system of bulkheads and valve gates control the transfer of water in these culverts during operation and maintenance. These gates are designed to withstand the hydrostatic and transient pressure loads. A phenomenon that is, however, usually overlooked in the design is the hydrodynamic pressure that is built up in the system during an earthquake. This pressure is caused by the seismic acceleration and could be higher than hydrostatic pressure in a severe earthquake. In this paper a set of simulation results using Abaqus/Explicit are presented for hydraulic culvert models to investigate the pressure caused by an earthquake.

Customer Papers

A ballasted railroad track consists of rails, fasteners, ties, ballast and the underlying subgrade. Realistic simulations of the track response to interactive vehicle-rail loads will require detailed models of each component. In this paper, finite element (FE) models are developed for some of the ballasted track components including wood and concrete crossties, ballast and subgrade. A user material subroutine is employed to predict the failure of wood ties based on an orthotropic stress criterion. The concrete tie is modeled as a heterogeneous medium with prestressing tendons embedded in a concrete matrix. The concrete material observes elasticity followed by damaged plasticity.

Customer Papers

At the heart of every simulation is a question about the natural world. The ultimate success of the simulation is then measured by how satisfactory the answer is afforded by the simulation. The objective of this paper is to present a case study of the simulation of a heart to illustrate the core issues to obtaining useful simulation results using finite element based numerical modeling and simulation. This paper will discuss the question on the interaction forces between the human heart and the valvular prosthesis to illustrate how the core issues are dealt with in the biomedical device numerical simulation practice.

Customer Papers

A product development and evaluation using the simulation technology now is a standard process. Approximation models are now frequently used as an efficient design tool. Isight, an automation and optimization tool of SIMULIA, offers a several methods to generate Approximation model. Using Approximation model, as it is well known, the exploration time can be shortened, especially when a simulation takes long time for a single run. Generally, it is important to provide effective sampling points as Teacher data. In most of methods, a sampling matrix is generated taking no account of any response and the more parameters one has, the more Teacher data one needs.

Customer Papers

The Suspension Assembly modeling in utility vehicles is a challenge in terms of representing various bushings used for joints and in general there are multiple bushings in any suspension assemblies. These bushings have typically hyper elastic material bonded between metal sleeves and thus nonlinear in behavior. Also, the joint is very likely coupled with bolt joint which causes additional complexity in capturing the local behavior of the joint. The connector elements available in Abaqus/Standard enables us to capture the appropriate Bushing stiffness in all three axes and the simplified bolt model can accurately capture the local coupled stiffness of the Bushing and Bolt joint. A simplified suspension assembly for upper control arm was analyzed, tested and correlated for loaddeflection data.

Customer Papers

The load rejection is regarded as a vital process for a steam turbine performing commission operation or encountering some emergent accidents. Under the combination of the boiler and the turbine control valve, the steam temperature could be rapidly reduced and the turbine load could be cut back. In order to analyze the stress of the steam turbine during load rejection, the first stage rotating blades and grooves are taken as research subjects and the commercial software “Abaqus” is employed to perform the FEA process.

Customer Papers

In recent years Fokker Landing Gear has developed a proprietary material model to more accurately model composites. In this material model the fibers and resin are included as separate materials with their own specific material and failure behavior, both with a limited number of material parameters and with clear physical meaning. The interaction between the fibers and resin is accounted for using a new analytical approach. Because the inclusion of fibers is done using a vector based approach the model is valid for any fiber structure.

Customer Papers

In the development of the new bi-level train KISS Abaqus/Standard and Abaqus/Explicit have been intensively applied to optimize the structure with respect to stiffness and strength as well as to crashworthiness. Models up to 3 million shell elements have been used to prove the strength of the load carrying structure with respect to the standard EN12663-1. By using Abaqus/Standard the calculation times were minimized allowing for a significant number of iterations to optimize the structure with respect to lightweight engineering and with respect to a reduction of manufacturing time. Additionally, the Abaqus/Standard result files were used to investigate the fatigue strength of the structure, especially of the welds, with FEMFAT, a postprocessor code from Magna Powertrain.

Customer Papers

Composite structures can be vulnerable to several types of damage. Abrasion and low to mid velocity impacts can result in deep scratches impacting the surface plies. In this study, the delamination which is induced by scratches under tensile loading are investigated using experimental and finite element techniques. A finite element approach based on progressive damage analysis implemented in VUMAT subroutine and a cohesive zone model using Abaqus are performed to simulate the behavior in the composite specimen. Scratches at different depths with different angles in carbon fiber-epoxy laminates are modeled to study the influence of the scratch size and the stacking sequence effects. Experimental results show the delamination propagates between layers.

Customer Papers

The use of renewable energy sources is being expanded strongly all over the world. Wind power plays an important role in this field. In recent years, the output of wind turbines has increased continuously. In such plants, the important mechanical components include bearings which, with increasing output, are becoming increasingly larger. Therefore the Schaeffler Group took the decision to build the largest bearing test rig in the world. This makes it possible to strongly drive forward the development of large size bearings for wind turbine manufacturers. With a maximum bearing outside diameter of approx. 3.5 m, the highly versatile test rig can also be used to test all other large size bearings.

Customer Papers

A discrete multi-mode damage initiation, propagation, and interaction tool is implemented within Abaqus’ implicit solver for residual strength and life prediction of bolted joints with a given initial damage resulting from the fabrication and installation process. A discrete crack network model (DCN) for damage progression prediction has been developed by combining mesh independent matrix cracking with cohesive zone delamination models at the ply interfaces. A regularized X-FEM (Rx-FEM) framework maintaining the distribution of the Gauss integration points without element slicing has been utilized for implementation of the solution module for residual strength prediction under monotonic loading.

Customer Papers

The goal of this work was to simulate both the flow in a rocket engine nozzle and the resulting flow-induced transient loads on the nozzle. This unsteady nozzle flow results in structural dynamic excitation, which contributes not only to nozzle stress and deformation but also to the dynamic loads that are transmitted to the rest of the engine. This paper demonstrates the capability of a coupled fluid-structure interaction (FSI) simulation for predicting side loads on a rocket engine nozzle. The capability was demonstrated using the space shuttle main engine (SSME) during a portion of the engine startup sequence.

Customer Papers