Normally for a surface mesh, edges are shared between adjacent triangular and rectangular meshes. For one edge, there are two surface meshes. However, depending on the analysis target, there are times when three or more surface meshes are adjacent, so you need to check them. How to check: 1. Go to Display 2. Select Multi from Options of the Display Grid panel 3. Click Display After performing these steps, regions where there are three or more adjacent surface meshes will be shown in yellow.