Learning Forum

[christoph.hecht]

Hello,

we are currently setting up a thermal-transient simulation and would like to define material properties as a function of temperature. This involves a melting process (selective laser melting) so that the thermal conductivity after melting (assumption: temperature > melting point in previous time steps) no longer corresponds to the thermal conductivity of the powder but to the thermal conductivity of the solid material. The powder layer is modelled as a thin layer with lower thermal conductivity than the bulk material. 

Is there a way within the thermal-transient-module to solve this issue?

Thanks in advance

[Rahul Kumbhar]

Hi Christoph,

In Workbench Engineering Data, it is possible to define temperature dependent Thermal conductivty.

In your case, the Thermal conductivity is changing after metling and solidifies. So after solidfication when body reaches to room temperature it should still use thermal conductivity of solid material. For this you can define two material models. Inbetween the loadsteps(transition from powder to melt), you can use MPCHG command to change the material of solid elements.

If you are using Workbench Mechanical, you can insert command object under analysis setting.

[Rahul Kumbhar]

Hi Christoph,

Another way I can think of is using element 'Birth and death' option. You can deactivate the particular elements for the laodsteps when it is powder. Then activate the elements using this option for the laodsteps where these are solid material.

[Akshay Maniyar]

Hi Christoph,

Are you trying to simulate any additive process? You can check the Ansys help link below for more details.

Ansys Product Help

Thanks,

Akshay Maniyar