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Hello everyone,
I’m trying to model a system that contains several thermosiphon units using Type 45a.
With Type 1, it’s possible to specify the number of collectors in the field directly. However, Type 45a seems to be structured as a single system block that would need to be replicated for each thermosiphon, which quickly becomes impractical.
Example:
Suppose I have 30 thermosiphons, each with a 3 m² collector and a 200 L storage tank.
A naïve approach would be to use a single Type 45a with 90 m² and 6000 L to represent the whole system, but this would not correctly capture the dynamic behaviour and non-linearity of the thermosiphon operation.
Replicating Type 45a thirty times, on the other hand, would make the Simulation Studio extremely cluttered.
Has anyone found a practical way to model such multi-unit thermosiphon systems efficiently? Any tips or workarounds would be much appreciated.
Thanks in advance!
Hello @ken,
This may be oversimplifying the problem, but if the 30 thermosiphon collectors are all in parallel and all have the same parameters and inputs, can you model a single collector, and use an equation block to multiply the total flow rate, useful energy gain, losses, etc. by 30?
If you do in fact need 30 units, unfortunately there's no quick and easy way to add and connect 30 identical units to a project. There are some tricks to make the process (a little) easier:
* If the units all have the same parameters, you can set the parameters as you wish for one unit, then copy/paste the unit (Ctrl+C Ctrl+V, or right click on the unit and select Copy, then right click in the project and select Paste) as many times as you like. You can also select multiple units and copy/paste a set of connected units (say a thermosiphon/load/thermostat combo) in the same manner.
* You can select multiple units and create a macro (Assembly -> Create macro, or click the green Create macro icon in the toolbar on the left side of the window) to turn those units into one conglomerate "unit." This can help maintain organization and reduce clutter in the overall project. Macros can also be copy/pasted just like an individual unit.
* If the limitation is the size of the project window, you can increase the project size by going to Assembly -> Settings -> Project, and changing the height and width of the project window to whatever you like.
Finally, if you're adept at coding, you could write a script in any programming language to write and run the .dck file (the text file that contains all the information TRNSYS needs to run the project), and bypass the Simulation Studio altogether. You can see the .dck file for any project you've run by navigating to that project's folder on your computer and opening the .dck file in any text editor. It would take some time to learn the .dck file syntax and set up the script, but might save you time in the long run if you anticipate changing the project multiple times or setting up multiple projects of this nature in the future. (You could also manually edit the .dck file to copy/paste the units and connections you want, but that may be more tedious than editing the project through the Simulation Studio). Note that if you do write or edit the .dck file with an outside program, it may not open (or be very pretty) in Simulation Studio; in other words, Simulation Studio can take a graphic representation of a project and create a .dck file, but it can't very well take a .dck file and create a graphic representation of a project.
Good luck!
Thank you very much @a_weiss for these suggestions. They represent several valuables options for me. Thanks
