openmodelica

问题 I would like to extend the functionality provided by Modelica Standard Library's types ExternalCombiTable1D and ExternalCombiTable2D , to implement an N-dimensional (linear) interpolation (with "N" up to at least 4, possibly getting up to 8) on external data tables (saved on txt data files). What would be the best way to do that? 回答1: You might wanna have a look at the current list of ideas for future extensions: https://github.com/modelica/Modelica/issues/1153 回答2: Dassault Systems has

问题 I am an OpenModelica beginner trying to model a DC/DC converter with constant voltage and current limiting. Basically the output is supposed to give a constant voltage until the maximum current is reached and then hold that current by reducing voltage. This is the equation part of my code so far: model DC_DC "Voltage source with current limiting" import SI = Modelica.SIunits; parameter SI.Voltage Vnom(start=1) "Value of nominal output voltage"; parameter SI.Current Inom(start=1) "Value for

问题 I am an OpenModelica beginner trying to model a DC/DC converter with constant voltage and current limiting. Basically the output is supposed to give a constant voltage until the maximum current is reached and then hold that current by reducing voltage. This is the equation part of my code so far: model DC_DC "Voltage source with current limiting" import SI = Modelica.SIunits; parameter SI.Voltage Vnom(start=1) "Value of nominal output voltage"; parameter SI.Current Inom(start=1) "Value for

问题 I'm trying to solve the code model modelTest // types type Mass = Real (unit = "Kg", min = 0); type Length = Real (unit = "m"); type Area = Real (unit = "m2", min = 0); type Force = Real (unit = "Kg.m/s2"); type Pressure = Real (unit = "Kg/m/s2"); type Torque = Real (unit = "Kg.m2/s2"); type Velocity = Real (unit = "m/s"); type Time = Real (unit = "s"); // constants constant Real pi = 2 * Modelica.Math.asin(1.0); parameter Mass Mp = 0.01; parameter Length r1 = 0.010; parameter Integer n = 3;

问题 Hi Modelica Community, I would like to run two models in parallel in JModelica but I'm not sure how to pass variables between the models. One model is a python model and the other is an EnergyPlusToFMU model. The examples in the JModelica documentation has the full simulation period inputs defined prior to the simulation of the model. I don't understand how one would configure a model that pauses for inputs, which is a key feature of FMUs and co-simulation. Can someone provide me with an

问题 I am currently doing a course called "Modeling of dynamic systems" and have been given the task of modeling a warm water tank in modelica with a distributed temperature description. Most of the tasks have gone well, and my group is left with the task of introducing the heat flux due to buoyancy effects into the model. Here is where we get stuck. the equation given is this: Given PDE But how do we discretize this into something we can use in modelica? The discretized version we ended up with

问题 I developed for the example a simple Modelica model based on the fluid library of the MSL. I connected a MassFlowSource with a pipe and a Boundary_PT as sink function as in the picture below: http://www.casimages.com/img.php?i=14061806120359130.png I generate a FMU package with OpenModelica (in mode model-exchange). I manage this FMU package with python with the code below: import pyfmi, os from pyfmi import load_fmu myModel = load_fmu('PathToFolder\\test3.fmu') res1 = myModel.simulate() #

问题 I'm new to OpenModelica and I've a few questions regarding the code of 'BouncingBall.mo' which is distributed with the software as example code. 1) what's the difference between 'when' and 'if' ? 2)what's the purpose of variable 'foo' in the code? 3)in line(15) - "when {h <= 0.0 and v <= 0.0,impact}" ,, shouldn't the expression for 'when' be enough as "{h <= 0.0 and v <= 0.0}" because this becomes TRUE when impact occurs, what's the purpose of impact (to me its redundant here) and what does

问题 I would like to motivate a question I asked before about a Modelica array of partial model. Consider the following model of a switch between 2 controllers. model Switch input Real u; input Integer sel; output Real y; protected Real x; equation if sel == 1 then y = 0.1 * (0 - u); der(x) = 0; else y = 0.1 * (0 - u) + 0.2 * x; der(x) = 0 - u; end if; end Switch; Let's ignore the fact that the PI controller may break when it is not selected for some time due to divergence of x . This can be fixed

问题 I am trying to simulate the flow in a pipe that starts out partially full, and gradually fills up. Once it is full, the flow equation needs to change. I have tried the following code, but I get a divide by zero error once the pipe is full. TestTrap1 is a demo that shows the problem. It seems that some equation is not correct once the pipe is full. I am using openmodelica to run this. package FlowPackage package Interfaces extends Modelica.Icons.InterfacesPackage; //Use this for a inlet outlet