Flow Cycle in Pipe System – Cycle Duration Twice as Long as Defined

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Hi everyone

I'm trying to simulate a flow cycle through a pipe system that runs through cold ground.

Goal: The pipes should be flushed with a warm fluid for 0.5 hours, then remain in the ground for 3.5 hours to release heat into the surrounding soil. I’ve implemented the flow cycle using both an Analytic Function and a Piecewise Function. The cycles appear to be defined correctly in both cases.

However, the inlet and outlet plots of the pipes clearly show that the cycle only repeats three times over the full simulation period – effectively running on an 8-hour rhythm instead of the intended 4-hour cycle. Model is in the Swisstransfer Link below because the attachment would have been too large: https://www.swisstransfer.com/d/647ba0ab-3e0b-4bcd-ae1c-d7beda8dff2d

What am I doing wrong?

Thanks for your help!



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