In ANSYS WB Mechanical, selecting appropriate boundary conditions is crucial for accurate structural analysis. A static support on one end can provide proper reaction forces but may lead to singularities at the edges, which can be ignored. A recommended approach is to kinematically constrain the block to allow deformation without rigid body motion, such as fixing a central node and applying zero translations at specific points. An alternative involves applying loads at the edges with no deformation constraints, which introduces "weak springs" to prevent rigid body motion. The preferred method ensures an idealized response, allowing the block to expand and deform naturally.