3D Example: Conduction Heating with Multiphysics

Foreword

This paragraph is a summary of cases treated in detail in the technical document: " 3D Conduction Heating with Multiphysics Technical Paper ".

The files relating to the studied cases, are accessible in the supervisor on the Open example context.

Studied device

The device to be analyzed is a micro gas sensor (heating circuit).

The studied device, represented in the figure below, includes the following elements:

  • heating element in platinium (electrode):
    • thickness: 10 μm
  • substrate of oxidized silicium:
    • thickness of Si: 200 μm
    • tickness of SiO2: 0.06 µm

Operating principle

The heating element – electrode – is supplied by a voltage source (1V).

We are interested in the temperature distribution in the plate.

Electric problem

The electric problem is briefly summarized below.

  • Geometry: The study domain contains only the electrode (the silicon substrate, the thin silicon oxide layer and the air are insulating regions that are not modeled).

  • Mesh: Mapped mesh at the base faces and extrusive mesh in thickness.

  • Physical properties:

Thermal problem

The thermal problem is briefly summarized below.

  • Geometry: The study domain contains the electrode, the substrate of silicon and the layer of silicon oxide (the surrounding air is not included).
  • Mesh: Automatic mesh at the base faces and extrusive mesh in thickness.

  • Physical properties:

    At this stage of the description, there is no heat source for the thermal problem.

Source

The source of heat is the current flowing through the electrode.

Studied case

Three studies are demonstrated:

  • study 1: single sequence between the Electric Conduction application and the Steady State Thermal application
  • study 2: multiphysics coupling between the Electric Conduction application and the Steady State Thermal application
  • study 3: multiphysics coupling between the Electric Conduction application and the Transient Thermal application

Study 1

Physical phenomena are considered independent – the thermal variations of the electric resistivity of platinum are not taken into consideration.

Study 2

Physical phenomena are considered interdependent – the thermal variations of the electric resistivity of platinum are taken into consideration.

Study 3

Physical phenomena are considered interdependent – the thermal variations of the electric resistivity of platinum are taken into consideration. The thermal application is transient.