#115: RBE3 and RBE2<\/p>\n
RBE2 (Rigid Body Element Type 2):
\nRepresents an infinitely stiff connection.
\nAll connected nodes (slave nodes) follow the exact same translations and rotations as the master node.
\nThere is no relative motion between the master and slave nodes.
\nCommonly used for rigid body constraints, fixtures, or modeling lumped mass regions.
\nAdds stiffness to the model\u2014use with caution in flexible structure simulations.<\/p>\n
RBE3 (Rigid Body Element Type 3):
\nA weighted interpolation element for distributing loads or mass.
\nDoes not add stiffness to the structure.
\nAllows slave nodes to move independently; only the forces are distributed based on weights or geometry.
\nOften used for load transfer, interface averaging, and pressure-to-point load mapping.
\nGood for preserving local flexibility while enforcing consistent load transfer.<\/p>\n
Key Differences:
\nFeature RBE2 RBE3
\nStiffness Adds infinite stiffness Does not add stiffness
\nDisplacement Slaves follow master exactly Slaves can deform independently
\nUsage Rigid connections Load or mass distribution
\nStructural Use Can be structural Not a structural element
\nTypical Use Fixtures, rigid joints Load mapping, averaging interfaces<\/p>\n
RBE2 is a rigid element which adds “infinite stiffness” to attached nodes which means both nodes to exactly the same displacements. There will be no relative displacement between the slaves.
\nRBE3 is an interpolation element used to distribute mass and loads depending on the length. RBE3’s aren’t really “rigid” and shouldn’t be used as structural elements. They are for distributing loads.<\/p>\n
RBE2 rigidly connects the master to the slave nodes. Basically, the slave nodes follow the same deformations as the master node.
\nRBE3 “flexibly” connects the master to the slave nodes. The master transmits a force to each slave node depending on its relative position to the master, thus allowing the slaves to deform differently compared to the master. Depending on the solver the force distribution may be weighted or altered based on DOFs.<\/p>\n","protected":false},"excerpt":{"rendered":"
#115: RBE3 and RBE2 RBE2 (Rigid Body Element Type 2): Represents an infinitely stiff connection. All connected nodes (slave nodes) follow the exact same translations and rotations as the master node. There is no relative motion between the master and slave nodes. Commonly used for rigid body constraints, fixtures, or modeling lumped mass regions. Adds […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","_lmt_disableupdate":"yes","_lmt_disable":"","jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[22],"tags":[42,325,326],"class_list":["post-673","post","type-post","status-publish","format-standard","hentry","category-nastran","tag-nastran","tag-rbe2","tag-rbe3"],"modified_by":"gantovnik","jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8bH0k-aR","jetpack_likes_enabled":true,"jetpack-related-posts":[{"id":2124,"url":"https:\/\/gantovnik.com\/bio-tips\/2024\/02\/413-1d-elements-in-hypermesh\/","url_meta":{"origin":673,"position":0},"title":"#413 1D elements in HyperMesh","author":"gantovnik","date":"2024-02-05","format":false,"excerpt":"Bar elements: Bar2 = Configuration 60 (1st order) elements with 2 nodes used to model axial, bending, and torsion behavior. 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