LS-DYNA Contact Instability and Penetration Troubleshooting 30 Cases - English Technical Courses - 031-Automotive Crash Testing & LS-DYNA Validation

Diagnose Initial Penetration in a Shell-to-Shell Contact

Build a minimal shell-to-shell impact model with a known initial gap violation, run LS-DYNA, and use contact energy and penetration depth output to confirm that the instability originates from initial penetration rather than time-step or material issues.

DiagnosePenetration

02

Resolve Initial Penetration by Adjusting Contact Thickness Offsets

Modify the shell contact thickness offset parameters in the same model to eliminate initial penetration, then compare contact force histories and energy error to verify that the penetration warning disappears without altering the intended physical gap.

PenetrationAdjusting

03

Detect and Fix Penetration Caused by Coarse Mesh in a Curved Contact Surface

Create a curved shell contact pair with deliberately coarse discretization, identify penetration at facet edges through contact gap output, and refine the mesh locally to show the reduction in penetration depth and contact force oscillation.

Penetrationdeliberately

04

Tune Penalty Stiffness to Suppress Contact Penetration Without Introducing Instability

Run a rigid-to-elastic impact case with default penalty stiffness, then vary the penalty scale factor and measure maximum penetration and contact energy ratio to find a stiffness range that removes penetration while avoiding high-frequency contact chatter.

StiffnessSuppress

05

Identify Soft Constraint Contact Instability from Excessive Penalty Stiffness

Force an overly large penalty stiffness in a deformable-to-deformable contact and use time-step and contact energy diagnostics to demonstrate the resulting numerical instability, then reduce stiffness to a stable value.

IdentifyConstraint

06

Resolve Penetration in a Segment-Based Contact with Sharp Corners

Model a sharp-cornered rigid tool contacting a deformable plate using segment-based contact, locate corner penetration through contact force spikes, and apply segment-based contact options or local geometry cleanup to eliminate the penetration.

PenetrationSegment-Based

07

Fix Penetration in a Single Surface Contact Due to Missing Contact Thickness

Set up a single surface contact on a thin shell assembly without contact thickness, observe interpenetration during folding, and enable the appropriate shell thickness treatment to restore correct contact behavior.

PenetrationThickness

08

Diagnose Penetration from Inconsistent Contact Entity Types in a Mixed Mesh

Build a contact definition mixing shell and solid elements, detect penetration at the shell-solid interface through contact gap output, and correct the contact entity type or add a tied contact to resolve the mismatch.

DiagnosePenetration

09

Eliminate Initial Penetration in an Assembly with Interference Fit

Create an assembly with intentional interference, use LS-DYNA initial penetration checking and contact offset options to separate the initial state, and verify that the interference is resolved without generating spurious contact forces.

EliminatePenetration

10

Resolve Contact Instability from Duplicate Contact Definitions

Define two overlapping contact pairs on the same surfaces, observe erratic contact forces and energy, and remove the duplicate definition to show the stabilization of the contact response.

InstabilityDuplicate

11

Fix Penetration Caused by Rigid Body Motion Exceeding Contact Search Frequency

Run a high-velocity rigid impact with a large contact search interval, detect missed contact and deep penetration, and reduce the search interval or enable automatic contact tracking to capture the contact event correctly.

PenetrationExceeding

12

Tune Contact Damping to Suppress Penetration-Induced Oscillation

Introduce viscous contact damping in a bouncing impact case, vary the damping coefficient, and evaluate penetration depth and rebound velocity to select a damping value that reduces oscillation without over-damping the physical response.

SuppressPenetration-Induced

13

Diagnose Penetration in a Tiebreak Contact Under Mixed-Mode Loading

Apply mixed-mode loading to a tiebreak contact, identify premature penetration or failure using contact stress and gap output, and adjust the tiebreak failure criterion or contact thickness to obtain physically consistent debonding.

DiagnosePenetration

14

Resolve Penetration in an Eroding Contact During Element Deletion

Model an impact with element erosion, observe penetration through the eroded region, and enable eroding contact options or adjust deletion criteria to maintain contact after element removal.

PenetrationDeletion

15

Fix Contact Instability from Zero or Negative Volume Elements at the Contact Interface

Create a model with distorted interface elements, detect negative volume or zero volume errors coincident with contact instability, and repair the mesh or adjust the time step to restore stable contact.

InstabilityNegative

16

Diagnose Penetration Caused by Incorrect Contact Surface Normal Direction

Define a contact surface with reversed normals, observe penetration or missing contact force, and correct the normal direction using LS-DYNA surface orientation tools to restore proper contact detection.

DiagnosePenetration

17

Resolve Penetration in a Self-Contacting Buckling Shell Structure

Induce buckling in a thin shell that contacts itself, identify self-penetration through contact gap output, and adjust the single surface contact parameters or mesh to eliminate the penetration while preserving the buckling mode.

PenetrationSelf-Contacting

18

Tune Contact for a Press-Fit Simulation to Avoid Initial Penetration and Excessive Force

Simulate a press-fit operation, use contact offset and interference removal options to avoid initial penetration, and verify that the insertion force matches the expected interference fit without numerical spikes.

Press-FitSimulation

19

Diagnose Penetration in a Spot Weld Contact Under Shear Loading

Model a spot weld using contact, apply shear loading, detect penetration or slip at the weld interface, and adjust the contact definition or add a tied contact to represent the weld correctly.

DiagnosePenetration

20

Resolve Contact Instability from Inconsistent Time Step and Contact Stiffness

Run an explicit analysis with a large time step and stiff contact, observe contact-induced instability, and reduce the time step or scale the contact stiffness to satisfy the stability condition.

InstabilityInconsistent

21

Fix Penetration in a Rigid Wall Contact with a Deformable Body

Impact a deformable body against a rigid wall with default settings, detect penetration through the wall, and adjust the rigid wall contact parameters or mesh to prevent penetration.

PenetrationDeformable

22

Diagnose Penetration in a Blast-Loaded Plate with Contact Between Fragments

Simulate a blast-loaded plate that fragments and contacts itself, identify penetration between fragments, and enable appropriate eroding contact or adjust contact thickness to maintain fragment interaction.

DiagnosePenetration

23

Resolve Contact Instability in a Crash Box with Folding Contact

Model a crash box under axial crushing, observe contact instability during folding, and tune contact parameters such as penalty stiffness and damping to achieve a stable folding pattern.

Instabilitycrushing

24

Fix Penetration in a Metal Forming Simulation with Tool Contact

Set up a deep drawing simulation, detect penetration between the blank and punch/die, and adjust contact thickness, penalty stiffness, or mesh to eliminate penetration while maintaining forming accuracy.

PenetrationSimulation

25

Diagnose Penetration in a Composite Delamination Contact

Model composite plies with contact interfaces, apply transverse load, detect penetration between plies, and adjust contact parameters or cohesive contact to prevent penetration while capturing delamination.

DiagnosePenetration

26

Resolve Contact Instability from Inconsistent Units in Contact Parameters

Introduce a unit inconsistency in contact stiffness or damping, observe penetration or instability, and correct the units to restore stable contact behavior.

InstabilityInconsistent

27

Fix Penetration in a Thermal-Mechanical Contact Analysis

Run a thermal-mechanical contact simulation, detect penetration due to thermal expansion, and adjust contact offset or thermal contact conductance to maintain contact without penetration.

PenetrationThermal-Mechanical

28

Diagnose Penetration in a Multi-Part Assembly with Contact Interference

Assemble multiple parts with slight interference, use LS-DYNA initial penetration checking and contact offset options to resolve interference, and verify that no spurious contact forces appear.

DiagnosePenetration

29

Resolve Contact Instability in a Drop Test Simulation with Multiple Contacts

Simulate a drop test with multiple contact pairs, identify penetration or instability at specific interfaces, and apply contact-specific fixes such as thickness offset or penalty scaling to stabilize the entire model.

InstabilitySimulation

30

Tune Contact Parameters for a High-Velocity Impact to Avoid Penetration and Instability

Perform a high-velocity impact simulation, vary contact penalty stiffness, damping, and search frequency, and evaluate penetration depth and contact energy to determine a robust parameter set that prevents penetration without introducing instability.

ParametersHigh-Velocity