Finite element analysis (FEA) of a composite overwrapped pressure vessel (COPV) has traditionally been a tedious and time consuming task. FEA is often omitted in the development of many vessels in favor of a “build and burst” philosophy based only on preliminary design with netting analysis. This is particularly true for small vessels or vessels that are not weight critical. The primary difficulty in FEA of a COPV is the creation of the model geometry on the sub-ply level.
Turon’s methodology for determining optimal analysis parameters for the simulation of progressive delamination is reviewed. Recommended procedures for determining analysis parameters for efficient delamination growth predictions using the Abaqus/Standard cohesive element and relatively coarse meshes are provided for single and mixed-mode loading.
Structures in general are subject to uncertainty due to manufacturing, assembly, environment of work, loads, etc … This scatter more specifically is associated for example to tolerances of thickness, position, waviness, etc, material mechanical properties distribution, layup alignment axes. All these deviations can be taken into account with stochastic analysis to reduce the total cost of the project considering all the phases of product life (manufacturing, assembly, maintainability…) and make a global robust design.
Thermal Barrier Coatings (TBC) have been used for almost three decades for heat insulation in high-temperature components to increase efficiency. Reliable diagnostic techniques that are practical to implement are needed to identify the location and severity of degradation in TBCs to protect against premature TBC failure. Luminescence spectroscopy has been utilized in detecting early damage, as it exhibits monotonic changes in the spectral characteristics with damage. Nevertheless there is still no agreement on what are the best spectral parameters that indicate damage.
Bird impact damage in complex aircraft structure has been investigated using explicit transient dynamic analysis by Abaqus/Explicit in order to fully employ its large library of elements, material models and the ability of implementing user defined materials. The numerical procedure has been applied on the very detailed large airplane secondary structure consisting of sandwich, composite and metallic structural items that have been modeled with 3D, shell and continuum shell elements, coupled with appropriate kinematic constraints.
Innovative composite structures are increasingly being used in the aircraft industry. A critical point of these new composite parts is the attachment to the surrounding aircraft structure. In cooperation between different EADS Business Units, a new advanced composite load introduction rib is developed to minimize weight and manufacturing costs. The new design of the flap focuses on the load introduction rib and drive fitting including the integrated lugs for the attachment to the flap support structure.
Boeing and Skyhook International entered into an agreement whereby Boeing will design and build two prototypes of the new Skyhook HLV aircraft. This hybrid airship is intended to carry 40 tons of cargo 100 miles. Due to the flexible, non-linear nature of fabric airship envelopes, as well as the complexity of designing a hybrid airship, the internal loads model for this aircraft is being developed in Abaqus and will be solved non-linearly.
Iam modelling a simply supported RC slab with Abaqus using Concrete Damaged Plasticity subjected to a concentrated load at the top surface of the slab. I have used element type C3D8R for concrete and truss elements to represent steel bars.
I found the result of FEM showed that the linear part of load versus deflection, i.e. from zero load up to yield load shows a very stiff curve compare to the experimental test results.
I mesh most of my parts in C3D8R. My simulation are quasi-static, and involve a lot of contacts. To model steel, I use a classic elastic-plastic behavior, coming from stress-strain curves we measured. I have the yield strength of the material and the strain at break. My questions concern post-processing.
Finally i found out the way to simulate PMMA embossing using Mooney Revlin constants at several tempature. Now i am trying to include Prony model and shift function with Hyperelastic model in ansys. I tried using static and transient analysis but it is not giving viscoelastic flow behaviour. If anyone done this kind of simulation in Ansys please help me. I am sending mooney revlin and prony model constants in ansys WB.
I am working on a 3D contact problem where a spherical part is pressed against another spherical surface. I was wondering what variables may be interesting to study for this problem. I decided to look at the contact area CAREA, the contact pressure CPRESS and the stress S but I am not able to find how Abaqus defines and calculates these variables, does anyone know?
Register for this FREE webinar to learn how the Abaqus Topology Optimization Module (ATOM), from Dassault Systemes SIMULIA, delivers advanced capabilities for nonlinear structural optimization and provides important benefits to engineers and product designers by identifying the optimized topology and shape of a structure.
Recently, I have worked on the creep crack growth coupled with CDM. In the references, it says that when the element reached to the critical damage, the E of the element was reduced to 0. However, when I used this method in my UMAT, it can achieved creep crack growth in some elements. As the number of damaged elements increases, the damaged eelments distorted too large,as shown in attachment. Therefore, the calculation is stoped.
I am trying to model concrete as an elastic material in ABAQUS. The model can be any simple structure (cube, beam or column) but the main feature is that concrete behaviour is elastic up to a limiting strain (St. Venant's theory). Which of the Failure criteria in ABAQUS i should be using (Elasticity or brittle cracking)? if neither would you mind explaining other options?
Leuven,Belgium, May 31, 2011. Materialise is proud to announce the newest release of the Mimics Innovation Suite. The software solution, already renowned for being the fastest and easiest method for getting accurate 3D surface models from imaging data, is now faster and more user-friendly than ever. An example of the improved features is that several