TRNpy: Parallelized TRNSYS simulation with Python

Simulate TRNSYS deck files in serial or parallel and use parametric tables to perform simulations for different sets of parameters. TRNpy helps to automate these and similar operations by providing functions to manipulate deck files and run TRNSYS simulations from a programmatic level.

Usage

TRNpy can be used as a standalone application or imported into other Python scripts. Please note that a its core it simply makes the command line call TRNExe.exe your_deck_file.dck. You still need your own, properly licensed, copy of the software TRNSYS to make this work. TRNpy is merely a wrapper or API to include TRNSYS simulations into your Python workflow.

Standalone TRNpy

TRNpy can be compiled into a Windows .exe file with the script setup_exe.py and the following tips are valid for trnpy_script.py and trnpy_script.exe.

• By double-clicking the program, the main() function of this script is executed. It performs the most common tasks possible with this application.

  • The first file dialog allows to choose one or multiple deck files to simulate.

  • The second file dialog allows to choose a parametric table, which can be an Excel or a csv file. The first row must contain names of parameters you want to change. The following rows must contain the values of those parameters for each simulation you want to perform. TRNpy will make the substitutions in the given deck file and perform all the simulations.

  • You can cancel the second dialog to perform regular simulations.

  • The parametric table could look like this, to modify two parameters defined in TRNSYS equations:

    Parameter_1	Parameter_2
    100	0
    100	1
    200	0
    200	1

• Running the program from a command line gives you more options, because you can use the built-in argument parser.

  • Type python trnpy_script.py --help or trnpy_script.exe --help to see the help message and an explanation of the available arguments.

  • This allows e.g. to enable parallel computing, hide the TRNSYS windows, suppress the parametric table file dialog, define the folder where parallel simulations are performed, and some more.

  • Example command:

    trnpy_script.exe --parallel --copy_files --n_cores 4 --table disabled

• Creating a shortcut to the executable is another practical approach

  • Arguments can be appended to the path in the Target field
  • Changing the field Start in to e.g. C:\Trnsys17\Work will always open the file dialogs in that folder

Module Import

Import trnpy.core into your own Python script. There you can initialize objects of the DCK_processor() and TRNExe() classes and use their functions. The first can create dck objects from regular TRNSYS input (deck) files and manipulate them, the latter can run simulations with the given dck objects. This also gives you the option to perform post-processing tasks with the simulation results (something that cannot be automated in the standalone version).

Installation

Windows Executable

If you received the precompiled trnpy_script.exe, just save the complete application folder anywhere. As explained, it makes sense to create shortcuts to the executable from your TRNSYS work folders. It can be compiled with setup_exe.py.

Python

If you want to use Python but do not yet have it installed, the easiest way to do that is by downloading and installing Anaconda from here: https://www.anaconda.com/download/ It's a package manager that distributes Python with data science packages.

During installation, please allow to add variables to $PATH (or do that manually afterwards.) This allows Python to be started via command line from every directory, which is very useful.

With an existing Python environment, you can use setup.py to install TRNpy into the appropriate place in your Python environment. Then you can import it into your own Python scripts.

Support

For questions and help, contact Joris Nettelstroth. If you would like to request or contribute changes, do the same.