In the documentation it is indicated, that cardinality() function is deprecated and should no longer be used. However, it is still used in the libraries such as ThermoSysPro. e.g. if (cardinalit...

I am designing a set of custom components for fluid system modelling. As there will only be one medium throughout the model, I want to be able to define that medium in one place. The system compone...

In order to make my model simulation's in Modelica run faster am asking the following quesion : What does impact simulation runtime in Modelica ? i will aprecicate any help possible.

Status of the post: 200313 Got an answer with code DEMO_v42 that I accept for the bounty! 200310 I comment on two key papers suggested yesterday. Still do not understand how to update DEMO_v41. ...

There are different Modelica Simulation Environments, including Dymola, Wolfram SystemModeler, OpenModelica, and Jmodelica. So, I try to load a thermal fluid library(ThermoSysPro https://github.com...

I am currently trying to simulate acoustic resonators using OpenModelica, and I am wondering how to robustly/nicely calculate their resonance frequency. As a simplified example (without Media, etc...

Task: I have a variable y1 whose derivative is driven by some law e.g. y1 = sin(time) and for which I set the starting value e.g. y1 = 3.0 I have a second variable y2 that is defined by y2 = y1 ...

I wanted to do the following in Modelica: in a specific model I have several parameters h and I want to deduce some time independent values k from them by solving a set of implicit equations betwee...

I noted numerical issues integrating a pulse input that is delayed by a fixed amount of time in Modelica (using Wolfram System Modeler 4.3): model PulseTest "Test FixedDelay with Pulse Input"; ...

This question has two main aspects actually. Right at the beginning, I have to admit that I am totally new to physical modeling and would be glad to be corrected as well, not only be answered. For ...

In Modelica I'm trying to define a dedicated data type OrifSizingCoeff for the sizing coefficient on an hydraulic orifice. The corresponding physical quantity is a volumetric flow rate divided by t...

I have an OpenModelica model made with OMEdit. In order to get a concrete example I designed the following: Now I would like to run the model in Python. I can do this by using OMPython. After im...

I would like to understand the general idea behind hybrid modelling (in particular state events) from a numerical point of view (although I am not a mathematician :)). Given the following Modelica ...

I'm creating a library of components in Modelica, and would appreciate some input on techniques for unit testing the package. So far I have a test package, consisting of a set of models, one per c...

Having run out of ideas again I turn to you. I'm sure this has to have been answered before though for the life of me I can't find a clear description of it. Scenario: You work hard to get a mod...

I would like to perform integration of a function of a variable other than time in Modelica, but I don't know how to do it. For example, how can I evaluate the integral of x dx with upper limit 5 a...