SIMULIA リソース・センター

The ability to accurately calculate the risk of fretting fatigue in the contact interfaces of clamped sub-assemblies in medium-speed diesel engines has become important as a consequence of, among other things, performance demands. The application of the finite element method to fretting fatigue risk evaluation is a demanding task because the contact has to be modeled very accurately with the help of, among other things, a very dense mesh to capture the steep stress gradient in a partial slip situation. A three-dimensional model of the contact between a counterweight and a crankshaft in a Wärtsilä diesel engine was made by using Abaqus.

Customer Papers

Typically thermo-mechanical analysis including complexities such as contacts and bolt preloads are carried out using three dimensional models. These analyses require significant time and effort in FE model building, analysis setup, solution, and results processing. It also requires special effort to ensure it is error free. This paper also talks about simplified yet almost equally accurate modeling and analysis method for thermo-mechanical analysis using brake fade test simulation as an example. This methodology is based on use of Abaqus/Standard Axisymmetric analysis technique modified to represent effect of discrete bolting, bolt preloads, and contacts within various components of the assembly.

Customer Papers

This work is concerned with the Abaqus implementation of a suitable CAE methodology to get the most benefits of structural adhesive bonding. In this study, we are interested in cohesive debonding where the adhesive thickness and its non-linear behavior are of major importance. When subjected to loading, significant stress field gradients may develop around outer edges of the joint. Because such regions are sites for failure initiation, a specific mesh refinement is needed. Using SIMULIA solutions, an efficient discretization strategy, inspired by the p-FEM, is suggested and is implemented as an Abaqus user element. As the approach is suggested to be used in real applications, a validation example has been chosen to show the suitability of the methodology on coarse meshes.

Customer Papers

Analysis methodologies developed for evaluating three threaded and coupled connectors quantitatively are presented. Two new non-dimensional parameters for assessing the seal leakage and load shoulder separation are introduced for the purpose. Stress Amplification Factor (SAF), defined in API Specification 16R, is scrutinized for what type of stress is to be used and which reference point the alternating stress is measured from. As a result of it, loading sequence Mean Tension with Two Alternating Moments (MT2AM) is proposed for SAF calculation.

Customer Papers

Electrostatic Discharge (ESD) is a phenomenon where static electricity discharge happens between two electrically charged objects when they come into contact with each other, such as the human body and an electronic device. This high voltage ESD pulse generated from the human body can enter the electronic device if touched, causing damage to IC circuits inside it. With increasing operating speed and decreasing operating voltage of electronic components the problem of ESD is a severe source of interference which can produce damage, upset or failure in electronic systems.

White Papers

The number of patients in need of medical aid devices (anti-decubital systems, medical shoes, orthoses etc.) has risen drastically due to demographic changes and an unhealthy lifestyle. Such devices however, are not always helpful at affected soft tissue body sites. Sometimes they even aggravate the situation, leading to costly complications such as pressure sores, infection and amputation. Therefore, better assessment and understanding of device caused mechanical loading, involving critical stress and strain at the affected tissue region, is essential to more effectively design such devices. A method to approach such problems has been developed.

Customer Papers

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