Using delay block in Simulink to account for flow rate in a fluid loop

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Bruce Beauchamp 2019-4-23

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/458082-using-delay-block-in-simulink-to-account-for-flow-rate-in-a-fluid-loop

I am trying to model a fairly simple cooling system loop where coolant flows over a battery to remove heat, then flows into a large reservoir where the coolant is mixed, coolant then flows out of the reservoir into a chiller which removes the added heat from the coolant.

In short, what I am experiencing is that with an initial system temp of 46C, the coolant rises to 60C within the first time step (when in reality it would take nearly 30 seconds for one volume of fluid to run through the battery). The same thing happens through the entire loop...the volume of fluid through the entire loop will take nearly 2 minutes to run through, but the whole system is updating every single time step, giving the impression that this huge thermal mass is able to reach equilibrium in less than one minute when it should likely take over an hour...

When I attempt to place delay blocks and change the sample time based on my understanding of this tool thus far, the whole simulation goes awry.

Is there a way to handle this using strategically placed delay blocks in my model? Or is there a better way to account for this?

I can't track down any information about how to use delay to model a real-life system without going into the control systems realm...

Any help would be greatly appreciated!