Dear all,
I like to model building energy use in an environment which does not limit me to pre-defined input data fields and keep code hidden in a black boxes. I like to have the option to go beyond the interface and be able to model odd design of buildings and HVAC solutions. However, I am not a computer programmer and why invent the entire wheel again. Therefor I look for a tool/environment which already has some building modules. I have been thinking about TRNSYS.
The Modelica language seems also very interesting. BERKELY lab has some building component library and moreover do I get the impression that Modelica is relatively easy to use and learn and do perhaps not require Master degree in programming to master.
Comments are welcome
Best regards
Jacob Lindblom
Should I learn Modelica?
Mar 11, 2013
Hi Jacob,
Just my 2 cents;
Disclaimer; I have only had contact with Modelica (some training,
conference, browsing), and much more TRNSYS experience.
If you were a consultant - looking to simulate new and existing buildings
and recommend energy retrofits for example, I would recommend TRNSYS over
Modelica. But because you need to create component models (no escaping
programming sorry), and because you are a researcher, you can definately
consider Modelica.
You're right, it's possible to do this in either TRNSYS or Modelica. The
learning curve for both would be comparable, in their own quirky ways.
Creating new components is also similar effort for both depending on the
component. You will definitely have to learn some programming concepts in
either case. I think however Modelica components have at least the
*potential* to be cleaner and more elegant than TRNSYS code.
TRNSYS has more component models, but you should really define exactly what
models you really need and compare both tools! Also check external
component libraries - TESS, Modelon...
Creating a complex building shape with windows, zones, etc. is probably
much easier in TRNSYS and it's 3D interface, so if you have complex
geometry, +1 point for TRNSYS.
Also important is training and local experts to ask about strange errors, I
should think you are well situated to get support for Modelica!
And then you must also consider the longevity and impact of your research -
Modelica is... fresher?
Cheers,
Marcus Jones, M.Sc., LEED?AP BD+C
Jacob
I second Marcus' comments and like to add the following:
The page
http://simulationresearch.lbl.gov/modelica/userGuide/gettingStarted.htmlhas
some pointers for how to get started with Modelica.
The tutorials on
http://simulationresearch.lbl.gov/modelica/releases/latest/help/Buildings_Examples_Tutorial.htmlshow
you what is involved in composing a model using existing component
models. Depending on your application, you may still need to develop some
own component models (typically by modifying existing models). In my view,
since you are a researcher, this is time well spent; Modelica is a language
whose user base is fast growing and the principle of equation-based
modeling is adopted by many system simulation programs.
For modeling building envelops, Modelica has currently limitations for
buildings with many rooms in terms of run-time. You therefore may want to
consider modeling the building envelop in E+, and linking it to Modelica
through the External Interface of E+, either through Functional Mockup
Units or through the Building Controls Virtual Test Bed.
All the best,
Michael