**Case Studies**** > Thermal**

## Case List

__Case 1: Heating Circuit__

Case 2: Heating Transistor

Case 3: Heating Circular Fins

Case 2: Heating Transistor

Case 3: Heating Circular Fins

**Case 1: Heating Circuit**

This model shows simulation of circuit heating process using COMSOL software. The circuit with a thickness of 10 µm is represented by membrane element and is assigned with a boundary heat resource. Heat flux conditions are set up on the top and bottom surfaces of the plate. The coupling analysis is executed with "Solid Mechanics", "Heat Transfer in Solids", "Membrane" and "Multiphysics" modules.

The distribution of stress, temperature, and isosurface temperature are predicted.

The distribution of stress, temperature, and isosurface temperature are predicted.

## Case 2: Heating Transistor

Thermal stress effects of a heating transistor can be simulated by coupling a heat transfer analysis and a structural mechanics analysis in COMSOL Multiphysics.

A convective heat flux with a heat transfer coefficient of 10 [W/m^2/K] is assigned to all the surfaces. The cylindrical block provides a linear heat source with a value of 5000 [W/m^3/K]. The 4 bolts are represented by 4 rigid connectors with fixed constraints to simplify the models. Tetrahedral elements are meshed for the whole model.

The temperature distribution and stress distribution are predicted.

A convective heat flux with a heat transfer coefficient of 10 [W/m^2/K] is assigned to all the surfaces. The cylindrical block provides a linear heat source with a value of 5000 [W/m^3/K]. The 4 bolts are represented by 4 rigid connectors with fixed constraints to simplify the models. Tetrahedral elements are meshed for the whole model.

The temperature distribution and stress distribution are predicted.

## Case 3: Heating Circular Fins

This case simulates the heating process of circular fins using COMSOL multiphysics. A domain heat resource is defined at the brick part. Heat flux conditions are set up on all surfaces only except the bottom surface of the brick part. The coupling analysis is executed with "Solid Mechanics", "Heat Transfer in Solids", and "Multiphysics" modules.

The distributions of stress and temperature are predicted.

The distributions of stress and temperature are predicted.