Reset boundary condition after a few runs

[Hfrossard]

Dear Sir,

I have a situation I want to run with several cycles.

As I cannot disclose my simulation, I will use sn example.

Suppose you have a metal pipe with a big thickness. Inside the pipe you have water entering always with 10°C and 10m/s and 0 Pa at the exit.

Externally to this pipe, you have some kind of polymer, like PVC or HDPE. This polymer has an initial temperature of 100°C.

This a cyclic process (transient) according to the following steps.

Time 0s - Polymer (initial temperatura of 100°C) in touch with the pipe (initial temperature of 25°C). Water starts flowing;

Time 10s - Polymer detaches from the pipe, with a resulting temperature after cooling. The pipe has also a resulting temperature, but the water keeps flowing;

Time 15s - From 10s to 15s, the pipe is cooled by the water, but at 15s, it gets in touch with a new polymer part with initial temperature of 100°C. The pipe has a diferente temperature from time 0 because of the first cycle.

Time 25s - Polymer detaches from the pipe. The cycle is repeated.

I want to run these cycles until I find the equilibrium.

How can I make this cyclic simulation? I don't know how to reset polymer temperature after 15s and keep the other temperature gradients as simulated in the previous cycle.

Best Regards,
Henrique

[Anonymous · Accepted solution]

Hi Henrique,

when you apply initial conditions after you already have a result set, you can chose an option to "re-initialize", which would be needed here.

Marco

[Hfrossard]

Hi Marco, Thank you very much. Actually I was trying to use "re-initialize" but it was not working. Than I discovered I was using it in a wrong way. Thank you for the tip. Best Regards!