{"id":250395,"date":"2023-02-17T13:48:06","date_gmt":"2023-02-17T13:48:06","guid":{"rendered":"\/forum\/forums\/topic\/reporting-an-error-in-anisotropic-elasticity-matrix-calculation\/"},"modified":"2023-02-17T13:48:06","modified_gmt":"2023-02-17T13:48:06","slug":"reporting-an-error-in-anisotropic-elasticity-matrix-calculation","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/reporting-an-error-in-anisotropic-elasticity-matrix-calculation\/","title":{"rendered":"Reporting an error in Anisotropic Elasticity Matrix calculation"},"content":{"rendered":"
Hi!<\/div>\n
 <\/div>\n
I want to notify you that your software calculates the D66 cell in Anisotropic Elasticity stiffness and compliance matrices incorrectly. When using Matrix Type Stiffness, Format IEEE, and Point Group 6mm, your software says that D66 = 2*(D11-D12), when in actuality it should be (D11-D12)\/2. Similarly, when using Matrix Type Compliance, Format IEEE, and Point Group 6mm, your software says that D66 = (D11-D12)\/2, when in actuality it should be 2*(D11-D12) (see https:\/\/ntrs.nasa.gov\/api\/citations\/20030014725\/downloads\/20030014725.pdf<\/a>).<\/div>\n
 <\/div>\n
Note that the unit of the stiffness matrix C is Pa and the unit of the compliance matrix S is Pa^(-1). Thus, one cannot simply switch the matrices’ names.<\/div>\n
\"Kuvan<\/div>\n
\"Kuvan<\/div>\n
I already contacted Ansys support about this error.<\/div>\n
 <\/div>\n
Regards,<\/div>\n
Katja<\/div>\n","protected":false},"template":"","class_list":["post-250395","topic","type-topic","status-closed","hentry"],"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\n\t\t\n\t\t\n\t\t