In modern earthquake engineering, design for seismic isolation has become increasingly important for the prevention of devastating damage in a major earthquake. One effective and practical method for seismic isolation is the use of friction pendulum bearings, of which many may be used in a bridge structure.
The ADINA User Interface (AUI) program offers comprehensive pre- and post-processing capabilities for the complete suite of ADINA Solution programs – Structures, Thermal, CFD, Electromagnetics and Multiphysics. However, other third-party pre- and post-processors can also work with the ADINA solvers and may offer certain advantages. For example, Femap contains interfaces to certain CAD packages not currently supported by the AUI, such as interfaces to ACIS, CATIA and Pro/ENGINEER (now called Creo Elements/Pro).
A shell structure is thin in one direction and long in the other two directions. Shell structures are used in a variety of architectural and industrial applications as they are lightweight, can span large areas, and can be designed to be strong and stiff. Examples of shell structures include stadium roofs, airplane fuselages, ship hulls, automobile hoods and body panels, bridge decks, and oil tanks.
The paper “CAE Applications in Hydraulics — Experimental and Analytical Study of a Check-Valve, L. Leventhal, SAE 03NVC-377” contains an interesting application of our fluid-structure interaction code ADINA-FSI. ADINA-FSI is used as the tool in a parametric study of check-valve design features, and the parametric study is the basis for an improved check-valve design. Also a comparison is made between experimental data and the results from ADINA-FSI, and the comparison is very good.
On the launch of ADINA version 9.4 (ADINA 9.4) one year ago, it was announced that the new ADINA sparse solver released in ADINA 9.4 achieves considerable speedups with no compromise in accuracy. This speed increase is of great value to industry — in particular, the automotive, aerospace, defense, industrial equipment, heavy machinery, civil, and consumer product industries — that frequently need to run large, high-fidelity simulations.
Shield tunneling using a large tunnel boring machine (TBM) is widely used to construct underground tunnels for subways. During tunneling, the soil strata substance is pressed, crushed, and removed by the TBM boring head. The shields, which are pushed along with the boring head, apply pressure on the newly created tunnel surface to stabilize it. After the boring head and the shields have advanced one lining width, a lining (pre-manufactured concrete ring segment) is installed. This procedure is often called a “launching” cycle in the industry. Thus, each launching will extend the tunnel by one lining width. A tunneling project can consist of thousands of launching cycles. The tunneling process substantially changes the geological conditions causing the surrounding strata to sag or uplift, which can affect the stability of existing tunnels nearby. Therefore, it is important to have an accurate assessment of the effect of tunneling. This blog post demonstrates how engineers and scientists of Zhongshan University (See the reference at the end of this blog post) applied ADINA software to evaluate the effect that the shield tunneling of the Guangzhou Zhujiang Xincheng underground automatic passenger mover (APM) system would have on the existing Guangzhou subway Line 1 tunnels.
The VOF surface-capturing method, available in ADINA 8.1, can be used to study the motion of bubbles due to buoyant and interfacial forces. The animation below shows the ascension of an air bubble in oil. Both the air and the oil are modeled as incompressible Newtonian fluids. The model is two-dimensional. The initial shape of the bubble is a 3 mm square. The oil container is 10 mm in width and 40 mm in height. The mesh has 17 x 67 quadrilateral FCBI (flow condition based interpolation) elements.
Robustness is an important requirement in nonlinear analysis. One of the requirements of a robust analysis code is that it obtains a realistic solution even with a coarse mesh. In engineering practice, the use of a coarse mesh should lead quickly to an approximate solution, especially in the case of a nonlinear analysis. There should be little need for experimenting with meshes just to obtain a realistic solution. Of course, with a robust analysis code, using a finer mesh always gives a more accurate solution.
A new meshing feature is present in ADINA 8.1 that enables the user to create a volume mesh from a collection of surface elements making up a closed volume. This is achieved without modifying the surface mesh. This feature is useful when a model is only represented by its external surface data (e.g., data from coordinate measuring machines, or CT scans). There are many potential applications, especially in the automotive and biomedical fields.