Time dependent temperature inputs

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juanbevan
Posts: 5
Joined: 30 Oct 2014, 16:02
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Time dependent temperature inputs

Post by juanbevan »

Hi All,

I am in the process of trying to implement a temperature cycling simulation to understand the thermal stress build-up on a material. Effectively, I am trying to have the material cyclically exposed to a fixed temperature for a fixed period of time (say at -55 °C for 30 minutes and then to 125 °C for 60 minutes) and then at the end of the simulation period (for example after 10 cycles) understand the impact that this temperature cycling has had on the material by evaluating the thermal stresses.

I have looked at the MATC Manual and thought of using the mathematical representation of a square wave to set the temperatures at the various time intervals by having the temperature set at each extreme for the relevant time periods. This seems like an over-complication for achieving what I want to do. Does anyone have any better suggestions? Are there any similar posts or examples? Given that I know the temperatures and time periods could I define this in a matrix form as an input to a boundary condition? I have browsed the forum but unfortunately have not been able to identify what I am looking for.

Any suggestions are greatly appreciated.
mzenker
Posts: 1999
Joined: 07 Dec 2009, 11:49
Location: Germany

Re: Time dependent temperature inputs

Post by mzenker »

Hi,

if the temperature is bodywise uniform, you can use Dirichlet boundary conditions on bodies. See Solver Manual, chapter 8.4. To make it time dependent, you can say

Temperature = Variable Time

followed by a table, a MATC expression or a user defined function call.

HTH,

Matthias
juanbevan
Posts: 5
Joined: 30 Oct 2014, 16:02
Antispam: Yes

Re: Time dependent temperature inputs

Post by juanbevan »

Hi Matthias,

Thank you for your reply.

I have read the Manual chapter 8.4 and whilst it helps I am not totally 100% clear on how to achieve what I want.

I have tried to define it as a table as below but I get the following error:
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Last edited by juanbevan on 23 Mar 2015, 19:31, edited 1 time in total.
mzenker
Posts: 1999
Joined: 07 Dec 2009, 11:49
Location: Germany

Re: Time dependent temperature inputs

Post by mzenker »

Hi,

there is an "End" missing at the end of your table.
See solver manual, "Keyword Syntax".

HTH,

Matthias
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