{"id":393964,"date":"2024-11-15T04:36:32","date_gmt":"2024-11-15T04:36:32","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/breast-deformation-from-prone-to-supine-position\/"},"modified":"2024-11-15T04:36:32","modified_gmt":"2024-11-15T04:36:32","slug":"breast-deformation-from-prone-to-supine-position","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/breast-deformation-from-prone-to-supine-position\/","title":{"rendered":"Breast deformation from prone to supine position"},"content":{"rendered":"

<p class=”MsoNormal” style=”text-indent: 24.0pt;”><span lang=”EN-US”>Recently, I attempted to simulate breast deformation from the prone to supine position, but I encountered some challenges. I’d appreciate any advice that might help.<\/span><\/p><p class=”MsoNormal” style=”text-indent: 24.0pt;”><span lang=”EN-US”>The model, segmented from MRI images, uses a Mooney-Rivlin hyperelastic material model with parameters shown below.<\/span><\/p><p class=”MsoNormal” style=”text-indent: 24.0pt;”><span lang=”EN-US”>*outside: skin, green: fat, orange; fibroglandular tissue, yellow: tumor, blue: pectoral muscle, gray: chest wall<\/span><\/p><p class=”MsoNormal” style=”text-indent: 24.0pt;”><span lang=”EN-US”> <\/span><\/p><p class=”MsoNormal” style=”text-indent: 24.0pt;”><span lang=”EN-US”>The mesh is tetrahedral, with a 3 mm element size. For contacts, I used the default settings in Workbench, except for a frictionless sliding contact between the pectoral muscle and chest wall; other contacts are set to “no separation.”<\/span><\/p><p class=”MsoNormal” style=”text-indent: 18.0pt;”><span lang=”EN-US”>The boundary conditions are based on configurations from several studies:<\/span><\/p><\/p>\n

    <li class=”MsoNormal” style=”mso-list: l0 level1 lfo1; tab-stops: list 36.0pt;”><span lang=”EN-US”>All faces of the chest wall are fixed.<\/span><\/li>\n

    <li class=”MsoNormal” style=”mso-list: l0 level1 lfo1; tab-stops: list 36.0pt;”><span lang=”EN-US”>The edge near the sternum is fixed.<\/span><\/li>\n

    <li class=”MsoNormal” style=”mso-list: l0 level1 lfo1; tab-stops: list 36.0pt;”><span lang=”EN-US”>Select nodes around the corners are fixed to prevent rigid displacement.<\/span><\/li>\n

    <li class=”MsoNormal” style=”mso-list: l0 level1 lfo1; tab-stops: list 36.0pt;”><span lang=”EN-US”>Nodes at the anterior end are constrained to deform only in the X and Y directions.<\/span><\/li>\n<\/ol>\n

    <p class=”MsoNormal” style=”text-indent: 18.0pt;”><span lang=”EN-US”>To simulate the prone-to-supine deformation, I applied twice the gravity on the model, enabling “large deflection” for the large expected displacement. The initial substeps were set to 100, with a minimum of 10 and a maximum of 1000.<\/span><\/p><p class=”MsoNormal” style=”text-indent: 18.0pt;”><span lang=”EN-US”>After these settings, the solution failed, producing error messages related to node 75601. I’ve tried several adjustments—reducing the mesh size to 1 mm, increasing “number of steps” to 20, and enabling “nonlinear adaptive region” for all bodies in the model—but these attempts did not resolve the errors.<\/span><\/p><p class=”MsoNormal” style=”text-indent: 18.0pt;”><span lang=”EN-US”><\/span><\/p><p class=”MsoNormal” style=”text-indent: 18.0pt;”><span lang=”EN-US”>I want to know the reasons for these persistent errors and want to get some suggestions to improve the simulation. I’d be very grateful for any advice. Thank you!<\/span><\/p><\/p>\n","protected":false},"template":"","class_list":["post-393964","topic","type-topic","status-publish","hentry","topic-tag-gravity-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