Dear All,

Short question

Here is my short question: How can I repeat a portion of a short solution that is on dynamic steady state? For example, in the following picture, the system took around 10 seconds before reaching the dynamic steady state. After that, everything just repeat periodically. However, since the field is still in motion, the solver does not take it as steady state and the time step is still very short. My expectation is to reuse one cycle of the solution (e.g. all variables between 33s to 39s) and fill them for the following times, so that a great amount of time can be saved.

Long Question

I am simulating a stirring tank with a cooling jacket. To simulate the magnetic stirring bar I used the component "Rotating Machinery, Laminar Flow", and "Heat Transfer in Fluids" for heat transfer. The geometry is shown in the picture below:

The simulation is acceptable (with time step 0.003s) but my simulation has a time span of hours (specifically, 1-2 hours). I found that the flow velocity field reached dynamic steady state after 1 second. After that, the velocity field just repeats itself for every revolution. However, the solver does not know the system is now on dynamic steady state and the time step is still small, making the simulation of whole time span almost impossible.

In my case the temperature does not affect the fluid property.

My expectation is to simulate the first 10 seconds for the flow field, and reuse the repeated solution for all the following time. Then, I can use this solution for computing the temperature field.

Can someone please give me some idea how to implement this operation?

Regards Yuanyi