Delayed Convection

Altair Forum User

Hi All,

 

I have a question involving the HyperMesh preprocessor. I'm trying to run a transient thermal analysis, where there is a consistent base boundary condition, and convection is applied, but only after a delay. I'm having a hard time figuring out how to apply convection partway through the analysis. For example, I'm allowing the part to heat for 25 seconds, and then turning a fan on and blowing on it for the last 25.

 

I have my TLOAD1, TABLED1, SPCD, and SPC collectors for convection, but I can't figure out how to apply this delay. I tried setting the TABLED1 value to 0 for the first 25 seconds, but that just sets temperature to zero I believe. I imagine the DELAY_OPTION would be helpful, but I don't know how. Thanks very much for any help you can provide.

Altair Forum User

Hi @b.blackford Please refer to DELAY card in OptiStruct help which defines the time delay for a dynamic analysis. 

Altair Forum User

 

Hi Prakash,

 

I've been trying to use delay, but it doesn't seem to be working. Applying a delay to the convection via the TLOAD1 collector hasn't been working to avoid convection in the first part of the analysis. Is it more complex than simply adding a numerical value for time delay? It seems like from the help menu that's all that's required, but it's not working for me.

 

Ben

Altair Forum User

Hi Ben,

 

I will check if there a way to delay and i will let you know soon. 

Altair Forum User

Thanks very much, I appreciate it!

Altair Forum User

Hi @b.blackford So delay is valid for structural only. I am checking if there is a workaround for delaying in thermal.