Ansys LS-DYNA
Multiphysics Solver

Ansys LS-DYNA is the industry-leading explicit simulation software used for applications like drop tests, impact and penetration, smashes and crashes, occupant safety, and more.

Simulate the Response of Materials to Short Periods of Severe Loading

Ansys LS-DYNA is the most used explicit simulation program in the world and is capable of simulating the response of materials to short periods of severe loading. Its many elements, contact formulations, material models and other controls can be used to simulate complex models with control over all the details of the problem. Ansys LS-DYNA applications include:

Ansys LS-DYNA: The Most Scalable Multi-Physics and Explicit Dynamics Software — Watch video

Quick Specs

LS-DYNA delivers a diverse array of analyses with extremely fast and efficient parallelization.

Impact Analysis

Forming Solutions

Euler, Lagrange, and ALE Formulations

Non-linear Implicit Structural Analysis

Crash Simulation and Analysis

Electromagnetics

Smoothed-Particle Hydrodynamics

Non-linear Explicit Structural Analysis

Failure Analysis

Fluid-structure interaction

Incompressible Fluid Dynamics

Total Human Model for Safety (THUMS™)

July 2024

What's New

The 2024 R2 release of Ansys LS-DYNA enables customers to increase efficiency throughout the full workflow for complex multiphysics simulations.

Simplified Input File Splitting

All sections of an LS-DYNA input file can now be easily split and saved into separate sub-input files for use inside and outside of Mechanical. Simplifying the process of modifying or extracting specific sections, such as a mesh, deformed geometry, or named selections, for reuse in subsequent simulations.

Streamlined Noise, Vibration, and Harshness (NVH) Simulations

Major enhancements to streamline NVH workflows with complex geometries using Boundary Element Method (BEM) acoustic analyses. These include a dedicated BEM acoustics meshing workflow to significantly reduce total meshing time and the integration of the BEM acoustics solver, which can evaluate high frequencies and large frequency ranges without the need to mesh the fluid volume.

Enhanced Multiphysics Simulations

Enhancements to multiphysics coupling enable increased accuracy when simulating the impact of structural and thermal induced deformations on electromagnetic components. Applications include battery modeling, electromagnetic forming, induction hardening, and more.

Sudden Impact: Simulating MMA Head Shots

Using simulation, doctors can determine the magnitude and location of brain strains, enabling them to improve concussion treatment.

By applying an LS-DYNA simulation-based workflow, clinicians can obtain a player’s acceleration level and convert that into strain levels across different parts of the brain.

Read the Article

Clinicians are unclear about how to measure the damage incurred by head impacts. Concussions diagnosed by magnetic resonance images (MRIs), computed tomography (CT) scans and blood tests often deliver inconclusive results.

Dr. Michael Power leads clinical care at Beaumont Hospital in Dublin, Ireland, which specializes in the treatment of head injuries — many of which occur during contact sports. Several years ago, he aligned with CADFEM Ireland — Ansys’ channel partner in Ireland — on a mission that would combine engineering simulation with clinical expertise to research the mechanisms of concussion. They sought to understand whether simulation software could help define the causes of concussions, reduce their number and improve concussion treatment.

LS-DYNA CAPABILITIES

Vast array of capabilities to simulate extreme deformation problems

Engineers can tackle simulations involving material failure and look at how the failure progresses through a part or through a system. Models with large amounts of parts or surfaces interacting with each other are also easily handled, and the interactions and load passing between complex behaviors are modeled accurately. Using computers with higher numbers of CPU cores can drastically reduce solution times.

Key Features

LS-DYNA elements, contact formulations, material models and other controls can be used to simulate complex models with control over all the details of the problem.

Implicit and Explicit Solvers
Frequency Domain Analysis
ICFD for Incompressible Fluid
Electromagnetics Solver
Multiphysics Solver
Particle Methods
Contact – Linear and Nonlinear
Adaptive Remeshing
Meshless – SPH and ALE
Advanced CAE
Supporting Tools

Implicit and Explicit Solvers

Easily switch between Implicit and Explicit solvers for your different runs.

Frequency Domain Analysis

Frequency domain analysis allows LS-Dyna users to explore capabilities such as frequency response function, steady state dynamics, random vibration, response spectrum analysis, acoustics BEM and FEM, and fatigue SSD and random vibration. You can use these capabilities for applications such as NVH, acoustic analysis, defense industry, fatigue analysis and earthquake engineering.

ICFD for Incompressible Fluid

ICFD solver is a stand-alone CFD code that includes a steady-state solver, transient solver, turbulence model for RANS/LES, free surface flows and isotropic/anisotropic porous media flow. Coupled to structural, EM solver and thermal solver.

Electromagnetics Solver

EM solves the Maxwell equations using FEM & BEM in the Eddy current approximation. This is suitable for cases where the propagation of electromagnetic waves in air (or vacuum) can be considered as instantaneous. The main applications are magnetic metal forming or welding, induced heating, and battery abuse simulation.

Multiphysics Solver

Multiphysics Solver include ICFD for Incompressible Fluids, electromagnetic solver, EM for battery abuse, and CESE for compressible fluids.

Particle Methods

There are several particle methods using LS-Dyna. AIRBAG_PARTICLE is used for for airbag gas particles which models the gas as a set of rigid particles in random motion. PARTICLE_BLAST for high explosive particles which models high explosive gas and air modeled Particle gas. Discrete element method includes applications such as agriculture and food handling, chemical and civil Engineering, mining, mineral processing.

Contact – Linear and Nonlinear

In LS-DYNA, a contact is defined by identifying (via parts, part sets, segment sets, and/or node sets) what locations are to be checked for potential penetration of a slave node through a master segment. A search for penetrations, using any of a number of different algorithms, is made every time. In the case of a penalty-based contact, when a penetration is found, a force proportional to the penetration depth is applied to resist, and ultimately eliminate the penetration. Rigid bodies may be included in any penalty-based contact but for that contact force to be realistically distributed, it is recommended that the mesh defining any rigid body be as fine as that of a deformable body.

Adaptive Remeshing

Several tools are provided for local refinement of the volume mesh in order to better capture mesh sensitive phenomenon’s such as turbulent eddies or boundary layer separation reattachment. During the geometry set up, the user can define surfaces that will be used by the mesher to specify a local mesh size inside the volume. If no internal mesh is used to specify the size, the mesher will use a linear interpolation of the surface sizes that define the volume enclosure.

Meshless SPH

SPH method in Ansys LS-DYNA® is coupled with the finite and discrete element methods, extending its range of applications to a variety of complex problems involving multiphysics interactions of explosion or fluid-structure interaction.

Meshless ALE

Ansys LS-DYNA has two different classes of mesh-free particle solvers: continuum-based smooth particle hydrodynamics (SPH), and discrete particle solvers using the discrete element method (DEM), the particle blast method (PBM) and the corpuscular particle method (CPM). These solvers are used in various applications like 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 impact on concrete and metal targets.

Advanced CAE

Peridynamics & SPG

The smoothed particle Galerkin (SPG) method is a new Lagrangian particle method for simulating the severe plastic deformation and material rupture taken place in ductile material failure. The Peridynamics method is another compelling method for brittle fracture analysis in isotropic materials as well as certain composites such as CFRP. These two numerical methods share a common feature in modeling the 3D material failure using a bond-based failure mechanism. Since the material erosion technique is no more necessary, the simulation of the material failure processes becomes very effective and stable.

Isogeometric Analysis (IGA)

The isogeometric paradigm employs basis functions from computer-aided design (CAD) for numerical analysis. The actual geometry of the CAD parts is preserved which is in sharp contrast to finite element analysis (FEA) where the geometry is approximated with, potentially higher-order, polynomials. Isogeometric analysis (IGA) has been extensively studied in the past few years in order to (1) reduce the effort of moving between design and analysis representations and (2) obtain higher-order accuracy through the higher-order interelement continuity of the spline basis functions used in CAD. LS-DYNA is the first commercial code to support IGA through the implementation of generalized elements and then keywords supporting non-uniform rational B-splines (NURBS). Many of the standard FEA capabilities, such as contact, spot-weld models, anisotropic constitutive laws, or frequency domain analysis, are readily available in LS-DYNA with new features added steadily.

Supporting Tools

LS-OPT

Ansys LS-OPT is a standalone design optimization and probabilistic analysis package with an interface to Ansys LS-DYNA. It is difficult to achieve an optimal design because design objectives are often in conflict. LS-OPT uses a systematic approach involving an inverse process for design optimization: First you specify the criteria and then you compute the best design according to a mathematical framework.

Probabilistic analysis is necessary when a design is subjected to structural and environmental input variations that cause a variation in response that may lead to undesirable behavior or failure. A probabilistic analysis, using multiple simulations, assesses the effect of the input variation on the response variation and determines the probability of failure.

Together, design optimization and probabilistic analysis help you to reach an optimal product design quickly and easily, saving time and money in the process.

Typical applications of LS-OPT include:

Design optimization
System identification
Probabilistic analysis

LS-TaSC

LS-TaSC™ is a Topology and Shape Computation tool. Developed for engineering analysts who need to optimize structures, LS-TaSC works with both the implicit and explicit solvers of LS-DYNA. LS-TaSC handles topology optimization of large nonlinear problems, involving dynamic loads and contact conditions.

Supporting Tools/LST Models

Dummies

Anthropomorphic Test Devices (ATDs), as known as "crash test dummies", are life-size mannequins equipped with sensors that measure forces, moments, displacements, and accelerations. These measurements can then be interpreted to predict the extent of injuries that a human would experience during an impact. Ideally, ATDs should behave like real human beings while being durable enough to produce consistent results across multiple impacts. There are a wide variety of ATDs available to represent different human sizes and shapes.

Barriers

LSTC offers several Offset Deformable Barrier (ODB) and Movable Deformable Barrier (MDB) models. LSTC ODB and MDB models are developed to correlate to several tests provided by our customers. These tests are proprietary data and are not currently available to the public.

Tires

LST jointly developed tire models with FCA. These models can be downloaded through the LST, Models download section. The models are based on a series of material, verification, and component level tests. The finite element mesh is based on 2D CAD data of the tire section. All major components of the tire use 8-noded hexahedron elements. The elastomers are modeled using *MAT_SIMPLIFIED_RUBBER and the plies are modeled using *MAT_ORTHOTROPIC_ELASTIC.