Simcenter STAR-CCM+ How to define Anisotropic Thermal conductivity in a cylindrical coordinate system?

Simcenter STAR-CCM+ Simcenter STAR-CCM+ Virtual Reality Teamcenter Share Simcenter Cloud HPC Simcenter STAR-CCM+ Viewer Simcenter STAR-CCM+ Application Specific Solutions


This article shows you how to apply Anisotropic thermal conductivity using a cylindrical coordinate system.


Simcenter STAR-CCM+ allows you to specify Anisotropic thermal conductivity for a material. There are several different ways the thermal conductivity is defined in Simcenter STAR-CCM+.
This article shows you how to define thermal conductivity in Radial, Theta, and Z-directions.

Standard materials in Simcenter STAR-CCM+ has thermal conductivity set to a constant value. To specify an Anisotropic thermal conductivity, select the material properties under physics continuum and change that to Anisotropic:
In the Region-Physics Values node now two new sub-node appears: Orientation Manager and Thermal Conductivity Orientation. In the Orientation Manager node one can specify the coordinate system to consider for the anisotropic thermal conductivity by adding a new local orientation with right-click --> new. 

Then the orientation can be specified to be the cylindrical coordinate system we have previously generated in the Local Coordinate Systems node. (See this page on how to create a local co-ordinate system) 
In case of multiple Local orientations in the Orientation Manager, the correct one can be selected on the Orientation node.
The objective is to define different thermal conductivity values in Radial, Tangential (Theta) and Axial directions. The example that is presented in this article consist of a cylindrical object with hot surfaces on the front face and circumferential surface. The geometry is misaligned from the local coordinate system as shown by the image below.
The thermal conductivity values can be defined as tensor quantities as desired. (See this page about tensor quantities). In this example we set the following tensor quantities:
k11 --> XX Component = Thermal Conductivity in Radial direction.
k22 --> YY Component = Thermal Conductivity in Tangential (theta) direction.
k33 --> ZZ Component = Thermal Conductivity in Axial direction.

Please note that setting the Thermal conductivity as Anisotropic and defining all other k-elements of the tensor as zero is equivalent with choosing the Orthotropic tensor.
To demonstrate that the thermal conductivities have been defined in the desired direction, you can visually test it by setting the thermal conductivity to be high in one direction and small in the other two directions. You see a greater increase in temperature in direction with higher thermal conductivity as compared to the other two directions. The images below show the increase in temperature after a few hundred iterations by setting a high conductivity of 1000 W/m-K in one direction and a low thermal conductivity of 0.1 W/m-K in the other two directions.

XX Component (Radial direction)
YY Component (Tangential direction)
image.png ZZ component (Axial direction)
A sim file demonstrating the setup is attached to this article.

See also:
How to create an anisotropic thermal conductivity with a field function
How to define an anisotropic thermal conductivity on a solid using a table?

Multi-Timescale CHT within a single simulation with Simulation Operations: Exhaust Manifold Example

Simcenter STAR-CCM+ Documentation sections:
User Guide >| Using Tools >| Coordinate Systems >| Coordinate Systems Reference

KB Article ID# KB000031622_EN_US



Associated Components

Design Manager Electronics Cooling In-Cylinder (STAR-ICE) Job Manager Simcenter STAR-CCM+