Ansys LS-DYNA is the world's most widely used explicit simulation program, capable of modeling the response of materials to short periods of intense loading. It features a variety of elements, contact formulations, material models, and other controls, allowing for detailed simulation of complex models.
Applications of Ansys LS-DYNA include:
LS-DYNA offers a wide range of analyses with exceptionally fast and efficient parallelization.
The 2024 R2 release of Ansys LS-DYNA allows customers to enhance efficiency across the entire workflow for complex multiphysics simulations.
All sections of an LS-DYNA input file can now be effortlessly divided and saved into separate sub-input files for use within and outside of Ansys Mechanical. This simplifies the process of modifying or extracting specific sections, such as a mesh, deformed geometry, or named selections, for reuse in future simulations.
Significant enhancements streamline NVH workflows with complex geometries using Boundary Element Method (BEM) acoustic analyses. These include a dedicated BEM acoustics meshing workflow that significantly reduces total meshing time and the integration of the BEM acoustics solver, which can assess high frequencies and large frequency ranges without needing to mesh the fluid volume.
Enhancements to multiphysics coupling improve accuracy when simulating the impact of structural and thermal-induced deformations on electromagnetic components. Applications include battery modeling, electromagnetic forming, induction hardening, and more.
Engineers can address simulations involving material failure and analyze how the failure progresses through a part or system. Models with numerous parts or surfaces interacting are also easily managed, accurately modeling the interactions and load transfer between complex behaviors. Utilizing computers with higher CPU core counts can significantly reduce solution times.
LS-DYNA elements, contact formulations, material models, and other controls allow for the simulation of complex models with precise control over all aspects of the problem.
Effortlessly alternate between Implicit and Explicit solvers to accommodate the varying needs of your different simulations.
Frequency domain analysis in LS-Dyna enables users to explore capabilities like frequency response function, steady state dynamics, random vibration, response spectrum analysis, acoustics BEM and FEM, and fatigue SSD and random vibration. These capabilities are invaluable for applications including NVH, acoustic analysis, defense industry, fatigue analysis, and earthquake engineering.
The ICFD solver is a standalone CFD code that features a steady-state solver, transient solver, turbulence model for RANS/LES, free surface flows, and isotropic/anisotropic porous media flow. It is coupled with structural, EM, and thermal solvers.
The EM solver addresses the Maxwell equations using FEM and BEM in the Eddy current approximation, suitable for scenarios where electromagnetic wave propagation in air (or vacuum) can be considered instantaneous. Key applications include magnetic metal forming or welding, induced heating, and battery abuse simulation.
The Multiphysics Solver includes ICFD for incompressible fluids, an electromagnetic solver for battery abuse (EM), and CESE for compressible fluids.
LS-DYNA offers several particle methods. The AIRBAG_PARTICLE method is used for modeling airbag gas particles, treating the gas as a set of rigid particles in random motion. PARTICLE_BLAST is used for high explosive particles, modeling high explosive gas and air as particle gas. The discrete element method (DEM) is applied in various fields, including agriculture and food handling, chemical and civil engineering, and mining and mineral processing.
In LS-DYNA, contact is defined by identifying locations to be checked for potential penetration of a slave node through a master segment using parts, part sets, segment sets, and/or node sets. Penetrations are searched for using various algorithms each time. In penalty-based contact, when a penetration is detected, a force proportional to the penetration depth is applied to resist and eventually eliminate the penetration. Rigid bodies can be included in any penalty-based contact; however, to ensure realistic force distribution, it is recommended that the mesh defining any rigid body be as fine as that of a deformable body.
Several tools are available for local refinement of the volume mesh to better capture mesh-sensitive phenomena, such as turbulent eddies or boundary layer separation reattachment. During geometry setup, users can define surfaces that the mesher will use to specify a local mesh size within the volume. If no internal mesh size is specified, the mesher will use a linear interpolation of the surface sizes that define the volume enclosure.
The SPH method in Ansys LS-DYNA® is integrated with finite and discrete element methods, broadening its application to complex problems involving multiphysics interactions such as explosions and fluid-structure interactions.
Ansys LS-DYNA offers two distinct classes of mesh-free particle solvers: continuum-based smooth particle hydrodynamics (SPH) and discrete particle solvers including the discrete element method (DEM), particle blast method (PBM), and corpuscular particle method (CPM). These solvers are employed in various applications such as hypervelocity impacts, explosions, friction stir welding, water wading, fracture analysis in car windshields, window glass and composite materials, metal friction drilling, metal machining, and high-velocity impacts on concrete and metal targets.
Peridynamics & SPG
The smoothed particle Galerkin (SPG) method is a novel Lagrangian particle approach for simulating severe plastic deformation and material rupture in ductile material failure. On the other hand, the Peridynamics method is highly effective for brittle fracture analysis in isotropic materials and certain composites like CFRP. Both methods share a common feature: modeling 3D material failure using a bond-based failure mechanism. This eliminates the need for material erosion techniques, making the simulation of material failure processes more efficient and stable.
Isogeometric Analysis (IGA)
The isogeometric paradigm uses basis functions from computer-aided design (CAD) for numerical analysis, preserving the actual geometry of CAD parts. This contrasts with finite element analysis (FEA), where the geometry is approximated with polynomials, potentially of higher order. Isogeometric analysis (IGA) has been widely studied to (1) reduce the effort of transitioning between design and analysis representations and (2) achieve higher-order accuracy through the higher-order interelement continuity of spline basis functions used in CAD. LS-DYNA is the first commercial code to support IGA by implementing generalized elements and keywords for non-uniform rational B-splines (NURBS). Many standard FEA capabilities, such as contact, spot-weld models, anisotropic constitutive laws, and frequency domain analysis, are readily available in LS-DYNA, with new features being continuously added.
LS-OPT
Ansys LS-OPT is a standalone design optimization and probabilistic analysis package that interfaces with Ansys LS-DYNA. Achieving an optimal design can be challenging due to conflicting design objectives. LS-OPT employs a systematic approach using an inverse process for design optimization: you first specify the criteria, then compute the best design according to a mathematical framework.
Probabilistic analysis is essential when a design is exposed to structural and environmental input variations that cause response variations, potentially leading to undesirable behavior or failure. By using multiple simulations, probabilistic analysis evaluates the impact of input variations on response variations and determines the probability of failure.
Together, design optimization and probabilistic analysis enable you to achieve an optimal product design quickly and easily, saving both time and money.
Typical applications of LS-OPT include:
LS-TaSC
LS-TaSC™ is a Topology and Shape Computation tool designed for engineering analysts who need to optimize structures. It works with both the implicit and explicit solvers of LS-DYNA, handling topology optimization of large nonlinear problems involving dynamic loads and contact conditions.
Dummies
Anthropomorphic Test Devices (ATDs), commonly known as "crash test dummies," are life-sized mannequins equipped with sensors that measure forces, moments, displacements, and accelerations. These measurements are used to predict the potential injuries a human might sustain during an impact. Ideally, ATDs should mimic real human behavior while being durable enough to produce consistent results across multiple impacts. Various ATDs are available to represent different human sizes and shapes.
Barriers
LSTC provides several Offset Deformable Barrier (ODB) and Movable Deformable Barrier (MDB) models. These models are developed to correlate with several proprietary tests conducted by our customers, and the data from these tests is not publicly available.
Tires
LSTC has collaborated with FCA to develop tire models that can be downloaded from the LST Models download section. These models are based on a series of material, verification, and component-level tests. The finite element mesh uses 2D CAD data of the tire section, with all major components modeled using 8-noded hexahedron elements. Elastomers are modeled with *MAT_SIMPLIFIED_RUBBER, while the plies are modeled using *MAT_ORTHOTROPIC_ELASTIC.
