Heart disease is among the leading causes of death in the Western world; hence, a deeper understanding of cardiac functioning will provide important insights for engineers and clinicians in treating cardiac pathologies. However, the heart also offers a significant set of unique challenges due to its extraordinary complexity. In this respect, some recent efforts have been made to be able to model the multiphysics of the heart using LS-DYNA.
Solder joints have become the main mechanical and electrical connections in modern microelectronics packaging for most consumer electronics products and they are typically observed to be the weakest links in terms for structural strength in the drop shock event. A drop shock simulation involves modeling the shock wave effect on mesoscale solder joints and macroscale chip packages concurrently, which is a typical multi-scale problem. Conventional finite element approaches using beam elements for the representation of the solders and the one-way sub-modeling technique cannot offer a high-fidelity solution. In addition, the shape of the solder ball is a very important contributory factor in determining the local stress levels and it is impractical to obtain all solder ball geometries by experimental measurement. Therefore, an effective simulation tool for the prediction of solder ball shape in the solder joint design as well as for the drop shock analysis is required in electronics industry.
The CHEMISTRY solver has been added to the LS-DYNA software, enabling users to model and predict accidental gas explosions in refinery plants, pipelines, and coal mines. Although this new solver has shown theoretical potential in chemical, oil and gas refineries, there are limited studies implementing the capabilities provided by the CHEMISTRY solver. In this study, a series of fundamental chemistry problems were simulated, to compare the numerical results with existing experimental data. This study finds excellent agreement between solver results and experimental data, proving a high level of precision obtained through the CHEMISTRY solver.
The LS-DYNA® Electromagnetic solver (EM) has recently integrated a new monolithic FEM (Finite Element Method) – BEM (Boundary Element Method) solver along with an AMS (Auxiliary Maxwell Space) preconditioner. Eddy-Current and Magnetostatic - including linear or non-linear magnetic materials - analysis can be done thanks to these new implementations [1]. On top of this, the capability to have permanent magnets has been introduced. We will start by showing a benchmark between LS-DYNA® and ANSYS Maxwell on the force calculation between two magnets in different conditions. The first model consists of two-cylinder magnets at a distance d. The magnet is a Neodymium Iron Boron magnet with a magnetic coercivity of -900 kA/m. In the first comparison, a linear magnetic characteristic of the magnet is considered. Then a non-linear BH curve is introduced in the next comparison. The insulator is a linear material with no conductivity. In the second model, we added a steel plate with high permeability between the 2 magnets to see its influence on the force on each magnet. The benchmark gives a good agreement between Ansys-Maxwell and LS-DYNA® in terms of results and computational cost in both linear and nonlinear case.
Core materials such as honeycomb core panels are used in various industrial products as lightweight and high stiffness materials. As one of the characteristics of the core panel, the sound absorption effect due to the core structure is expected. By using a large core panel for a soundproof wall such as a highway, the possibility of producing a soundproof wall that is lighter than the conventional soundproof wall and has a high sound insulation/absorption effect is being studied. In addition, with the electrification of automobiles, further quietness in the passenger compartment is required, and the use of core panels is being considered for improving the quietness of various transportation machines such as automobiles. Therefore, in this research, we assume several types of core shapes and compare the sound absorption effect of the core panel by modeling the interaction between the core panel and the sound in the air using ALE-based FEM in LS-DYNA®.
Previous implementations of LS-DYNA’s EM module have relied on an explicit scheme, requiring very small time-step sizes and therefore long simulation times. Recently, a new magnetostatic solver/ AMS preconditioner has been developed in LS-DYNA®. Unlike the current implementation, the new solver is unconditionally stable with respect to the time-step size and allows for the handling of materials with high permeability and low electrical conductivity. In this paper, the capabilities of the new solver is tested on the use-case of carbon fiber reinforced thermoplastic composite (CFRTPC) laminate induction heating using magnetic flux concentrators/field formers. In the current work, induction heating characterization experiments were performed on carbon fiber poly(ether ether ketone) (CF/PEEK) laminates using two different coil geometries.
Flow drilling is an alternative drilling solution for metal plates up to several centimeters. Using a conical tool, the process combines high rotation speed and high pressure to initiate friction and heat up the plate material locally in contact with the tool. As a consequence, the heated material has its mechanical characteristics reduced and is subjected to a very large plastic deformation. The surplus of matter is not wasted but is shaped into a collar above the metal plate and a socket below. These bulges induce a local additional thickness enabling a direct threading without added parts (bolt...).
Granular column collapse is a commonly studied granular flow problem, where an initially cylindrical column of dry granular materials collapses onto a flat surface under gravity. In this study, the meshless method Smoothed Particle Hydrodynamics (SPH) is used to model this phenomenon examining in particular the effect of aspect ratio, defined as the ratio of the initial height h0 and radius r0 of granular column. The numerical results are consistent with experimental results in terms of three aspects: (1) description of flow shapes; (2) runout distance and (3) final deposit height. Further observations and measurements are obtained to explore the collapse.
The launching process of ships is always a critical event during its construction. Especially a sideways launching process can be challenging. Besides high loads on the ship’s hull structure at the impact with the water surface, the stability has to be checked carefully to prevent capsizing of the ship. The resulting maximum heeling angle is one of the most critical parameters during such a launching process. If the maximum heeling angle gets too high, the ship can capsize or higher openings (e.g. ventilations) can come in contact with the water resulting in flooding of compartments. Therefore, the movement of the ship and the loads at impact with the water surface have to be assessed as accurately as possible during the design of a ship, if a sideways launching process is planned.
Conventional metal deformation simulations which include microstructure evolution would not consider any initial spatial variations but assume a uniform microstructure. In metal manufacturing, the liquid phase during casting and its subsequent solidification play major roles in characterizing the material properties (both micro- and macroscopic). Physics-based material models allow to simulate microstructural effects based on measurable microstructural properties. However, some parameters such as the grain size vary considerably within the manufactured part geometry depending on the processing conditions. Since the grain size distribution influences the microstructure evolution during subsequent heat treatment (HT) and metal forming operations, considering a more realistic initial distribution can be beneficial for subsequent simulations.
Since 2017 TAILSIT has maintained a close collaboration with Ansys/LST, formerly LSTC. Our partnership focuses mainly on the enhancement of LS-DYNA's electromagnetic (EM) solver module which is based on a coupling between Finite Elements (FEM) and Boundary Element Methods (BEM). This approach makes the EM solver highly suited for multiphysics problems. Prominent examples are, e.g., the simulation of parts moved by electromagnetic forces as well as processes like metal forming, welding, and induction heating.
There is a need for transitioning to an energy system with less greenhouse gas emissions and more sustainable energy production and consumption. A long-term structural change in energy systems is needed. Germany and France, among other countries, have decided to scale up the green hydrogen sector, with fundings of 9 billion and 7 billion euros respectively in the next 10 years.
Cardiac Electrophysiology using LS-DYNA®