To achieve the most accurate simulation results, mesh three-dimensional models with hexahedral elements. However, except for relatively simple and moderately complex geometry, it might not be feasible to partition the entire solid part into hex-meshable volumes. Volumes that are sweepable are meshed with hex elements (and, optionally, a small number of wedge elements) using a sweep meshing technique. Rectangular volumes are filled with fully regular hex elements. Other volumes are filled with predominantly tet elements. By default, the app generates tie constraints to provide compatibility between the tet meshes and the adjacent hex-dominant meshes. Alternatively, you can create a fully conforming linear mesh by placing a layer of pyramid elements along the interfaces with the adjacent sweep or structured volumes. You must use the CATIA Simulation Model Preparation app to partition a solid part into multiple volumes. The accuracy of the finite element simulation depends on the order of the elements used. First-order tetrahedral elements produce poor results when they are compared with first-order hex elements. Therefore, by default, the app fills non-sweep and non-structured volumes with second-order tets. | ||||||