Example Heat Conduction With a Hole

Next introduce a hole in the middle of the same diagram. The boundary conditions on the sides of the hole are thermal insulation. 

Step 1 Select the menu Draw/Specify Objects and select a square. Set the width to 0.4. and e corner to x = 0.3 and y = 0.3. Then choose Draw/Create Composite Object set the formula Al — R2. This causes the domain to be the large one (Al) minus the small one (A2). You can make very complicated domains by adding and subtracting various objects. 

Step 2 Create the mesh, with 824 elements and 1732 degrees of freedom. 

Step 3 Set the boundary conditions by selecting the menu Physics/Boundary Settings. The inner boundary is formed from boundary segments 4-7 select them and set Thermal Insulation. The right-hand boundary is now boundary segment 8, and you set it to Thermal Insulation as before. 

Step 5 If desired, you can choose the Postprocessing/Boundaiy Integration option and 

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