Automatic Coupling
?Entire Surface of Lagrange Part automatically interacts with Euler
?Euler exerts pressure on Lagrange
–Euler pressures are integrated over Lagrange surface areas to obtain nodal forces
?Lagrange acts as a flow constraint for Euler
–No friction between Lagrange and Euler Parts
?Partially covered Euler cells are automatically Blended
?Automatic coupling can be used with Erosion
Euler Flow Constraints
?Lagrange Parts impose flow constraints on Euler Parts by covering volumes and faces in the Euler grid
–Lagrange thickness must be larger than Euler cell size for flow constraints to functionproperly
–Lagrange element size should be larger than Euler cell size for smoothest coupling
?2:1 ratio recommended
Polygon Coupling
?Only available for 2D Euler
?Polygon acts as a flow constraint for Euler
–No friction between Polygons and Euler Parts
?Polygon points can be fixed (anchored) or attached to Lagrange surface nodes
?Polygon coupling must be used for Euler–Shell interactions in 2D
–Automatic coupling is usually preferable (and easier) if no Euler–Shell interactions are
required
?Polygon coupling cannot be used with Erosion
Polygon Examples
Menu for 2D Models
?Coupling Types
–None
–Automatic (polygon free)
?Easy to use
?Can be used with erosion
?Must be used for all Parts
?Cannot be used with Shell Parts (no thickened Shells)
–Polygons
?Cannot be used with erosion
?Can be used for Lagrange, ALE and Shell Parts
?No Euler subcycling
Example: Blast Wave on Deforming Wall (2D)
Example: Explosive Demolition of Concrete (2D)
?Multi-material Euler Part : HE + Air
?Lagrange Part : Concrete
Contact, Erosion and Coupling
?Contact, Erosion and Coupling can be used simultaneously in an analysis (must use automatic coupling)
–Failure and fragmentation of components
–Venting of fluids / gases through failed / fragmented components
–Combined shock (blast) and impact (fragment) loading of structures
?Major advantage over other programs
http://www.cadfamily.com/html/Article/ANSYS%20AUTODYN%20Euler-Lagrange%20Interactions_645_1.htm
http://www.cadfamily.com/html/Article/ANSYS%20AUTODYN%20Euler-Lagrange%20Interactions_645_2.htm
http://www.cadfamily.com/html/Article/ANSYS%20AUTODYN%20Euler-Lagrange%20Interactions_645_3.htm
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