{"id":397110,"date":"2024-12-11T14:49:04","date_gmt":"2024-12-11T14:49:04","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/to-shell-or-not-to-shell-that-is-the-question\/"},"modified":"2025-01-09T14:23:03","modified_gmt":"2025-01-09T14:23:03","slug":"to-shell-or-not-to-shell-that-is-the-question","status":"answered","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/to-shell-or-not-to-shell-that-is-the-question\/","title":{"rendered":"To shell or not to shell, that is the question."},"content":{"rendered":"

<p>Hello,<\/p><p>I need some guidance related to shell elements formulation. I know that they only have membrane and bending stresses, and it does not have a stress in the normal direction (thickness wise), but what does it means or what implications it has? Just that they have zero stress in that direction (Which I understand that by definition the thickness of a plane is zero) or that they cannot transfer any force in that direction?<\/p><p>The reason I´m asking is because I´m doing a static analysis for a two-part structure composed of square beams connected by 4 bolts and nuts. I`m meanly interested in contact area of the washer and the beam to see if it will endure the loads and fatigue. The thing is I can´t use solid element for obvious reasons and shell elements…. well, I´m having my doubts after checking the contact pressure result in those elements and it has literally zero. It made me think that the contact is detected but no force is tranfer through it. I have results and the deformation is how I expected to happen, but I´m not sure how condifent should I be.<\/p><p>Writing this post made me think… Can it be that it has zero contact pressure because it´s in the normal direction but the force is transmited via displacement of the other elements, like the bolt shaft? <\/p><p>PD: The forces are applied in the upper structure in those imprints you see in the first picture. The shaft and the washers and solids, everything else is shell.<\/p><p> <\/p><p><\/p><p><\/p><\/p>\n","protected":false},"template":"","class_list":["post-397110","topic","type-topic","status-answered","hentry","topic-tag-ansysworkbench-ansys-staticstructural","topic-tag-mechanical","topic-tag-shellsolidcontact-1"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t