A person specific drop foot brace was simulated in the commercial finite element code Abaqus.The geometry was imported from a 3D optical scan of the actual surface and modeled as a composite material layup defined in a local discrete material coordinate system. The finite
element model was used in order to model the stance phase in a normal walking. The material
choice is a challenging task giving flexibility to the brace together with sufficiently stiffness and
fatigue strength. The simulation has been compared with measurements from a strain gauge
mounted foot brace tested in use. Based on simulations, a large number of expensive trial and
For clinicians and medical device manufacturers, in-vitro and in-vivo testing of the knee are important methods for evaluating treatment techniques. However, numerical models that can provide much of the same information will become of more service and are a new focus of the modeling community. A continued effort has centered on specimen-specific anatomical and functional models, in terms of both geometry and mechanical properties of the tissue constituents.
A variety of polymers are used extensively for both medical applications and consumer products. Most of these polymers exhibit time-dependant behavior which varies significantly with environmental conditions. Injection molding technologies generally offer application design freedom and options for several functions build into each component. Meanwhile analysts are often faced with the difficulties of predicting the response of the final product.
Numerical methods applicable to the tibia bone and soft tissue biomechanics of an ACL reconstructed knee are presented in this paper. The aim is to achieve a better understanding of the mechanics of an ACL reconstructed knee. The paper describes the methodology applied in the development of an anatomically detailed three-dimensional ACL reconstructed knee model for finite element analysis from medical image data obtained from a CT scan. Density segmentation techniques are used to geometrically define the knee bone structure and the encapsulated soft tissues configuration.
As the maximum speed of bullet trains continues to increase, overheating and thermal deformation/stress on brake systems are going to be critical for emergency stops. Precise prediction of the maximum temperature is needed for the design of brake systems, especially for both discs and linings, where how to handle the high speed spinning of discs is the point of the heat/structure coupled analyses. Abaqus provides couple of potential methods but each one had critical shortcomings.
Electrically operated high temperature furnaces and reactors are used in many industrial
manufacturing processes such as sintering or single crystal growth in order to allow for the
required process conditions. In view of their outstanding characteristics refractory metals are
Today manufacturing companies are more and more often characterized by a growing product
and processes complexity. Projects needs the participation of a pool of companies that have to
collaborate in a multidisciplinary and integrated way following a defined PLM strategy.
These challenges are meant to introduce a new way of working, based on innovation and
global collaboration, both internally among different disciplines and externally between
operations, administration, and maintenance and its suppliers. The development engineering
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, e.g.: PUCK, JELTSCH-FRICKER or LaRC04.
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.
With the trend towards miniaturization and multi-functionality in products such as mobile electronic devices, miniature IC packaging such as fine pitch Ball Grid Array (BGA) package and Chip Size Package (CSP) are increasingly being used. However, the inherent vulnerability of these miniature IC packagings has brought along new reliability problems. Among them, the drop/impact robustness is the most challenging in terms of testing and designing.
A printer chassis provides an important function of locating and securing the relative position of all the sub-systems that makeup a printer. The customer location could be thousands of miles away from the factory and many modes of transportation are required from ship, train, trucks, forklift, to pushing across corridors, stairs and elevators. The transportation loads are the most sever the printer would see in its life time. These include impacts on all sides at 3 MPH to an 8 inch vertical drop.
Random response analysis is a linear approach, while most real life random vibrations involve nonlinear components. It is challenge to analyze a nonlinear system subjected to random vibration. This paper presents an Abaqus FEA approach on the fatigue life calculation of an automobile assembly with rubber isolators subjected to random vibration. Random loading is categorized using Power Spectral Density (PSD). An equivalent dynamic analysis or a random response analysis was used to obtain the maximum stress level and location from random vibration.
Consumers demand smaller electronics devices with more features and capabilities. Making devices smaller provides challenges to engineers to maintain the acoustic performances as enclosed acoustic volume sizes are reduced. This paper discusses the requirements for coupled
structural-acoustic simulation and demonstrates the application of this technology to cell-phone
CAE applications in dealing with multiphysics problems have been drawing much attention in product development in recent years. In particular, structure-fluid interaction (FSI) problems are of major concern. In this article, a numerical simulation on air squeeze-film damping which is important in MEMS design is presented. The study employs Abaqus and STAR-CD to perform a structure-fluid co-simulation. The squeeze-film damping phenomenon of a simple plate structure is demonstrated and its mechanism investigated.
For high strength carbon fiber reinforced polymers, the design criteria are often specified by the compression strength of the composite materials component. This is due to the fact that the compression strength of unidirectional composites is as low as 50 to 60 percent of the tensile strength. One important compressive failure mode in composite is kink-band formation which for a great deal is governed by the waviness of the fibers and the yielding properties of the matrix material.
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.
The production of hydrocarbons from deepwater reservoirs requires the fabrication and installation of massive infrastructure. As the global energy industry targets hydrocarbon reservoirs in ever deeper water, the use of remote subsea wells to access the reserves and deepwater flowlines to transport the produced hydrocarbons back to floating production platforms will increase.
Since its introduction in the 1960s, coiled tubing (CT) has evolved from smaller sizes and a few cleanout jobs to larger diameters and heavier grades with higher flow rates. Some of the limiting factors, especially on offshore platforms, are limited crane-weight capability and poor weather conditions, which severely limit the size of the reel that can be lifted. With offshore crane capabilities as low as eight tons on some platforms, a CT reel is often transported in two or more sections, requiring offshore assembly.
Offshore containers are exposed to the movement caused by wind, ocean currents, and unpredictable weather conditions so a good structural resistance is required for them. A dynamic analysis has been developed using Abaqus/Explicit to study the structural response of a horizontal pressure vessel mounted in Floating Production Storage and Offloading (FPSO) topsides in the Gulf of Mexico (GOM) coast. The model includes fluid behavior of crude oil inside the container for which the linear Us-Up Hugoniot equation of state is used. The viscosity of the oil was varied according to temperature.
Solar trackers are being increasingly used within the industry in order to improve the amount of power produced by photovoltaic systems. The design of these devices must pay special attention to wind action as the most relevant load seen by the generally flexible structure supporting the panels. However, standard building codes may not be particularly suitable for this sort of very flexible, extremely wind-exposed and not very critical-from-a-safety-point-of-view structures.
Cylindrical tanks are subjected to the seismic loads in certain countries, for example in Japan. The sloshing of these tanks is very important to consider the integrity of the containers. This phenomenon, however, is an interaction of structure and the fluid, namely oil, and is difficult to be analyzed using computer simulation codes. Owing to the FSI capability of Abaqus and Fluent via MpCCI, the phenomenon has been within the range of simulation. Authors tried to analyze the sloshing using the real seismic acceleration at Hachinohe earthquake in Japan and report the result.
A recent breakthrough in the development of shape memory materials has demonstrated promising applications for completion products in the oil and gas industry. In one of the targeted applications, shape modification is a major step toward commercialization of this technology. Efficiently and effectively reshaping the material is a key element for final production. The goal of our technical team is to design and optimize the reshaping equipment so as to enable production quantities of tools while maintaining material properties.
Seismic response of liquid storage tank floating roofs involve phenomena that require dynamic nonlinear geometric and material behavior as well as surface to surface contact. Good engineering practice requires a practical analytical approach that captures the essential ingredients of structural behavior under earthquake excitation by making reasonable, conservative, and manageable approximations to the actual conditions. This paper discusses an approach used in Abaqus to calculate the stresses and deformations of a liquid storage tank floating roof under seismic loading.