dymola

问题 I would like to simulate 3 pumps and a pressure sink. The problem now is if I want the pump to pump the medium in the opposite direction(backflow), the orifice does not work anymore... Can anyone please help me? Picture of the model Picture of the signal This is the error message: Log-file of program ./dymosim (generated: Thu Mar 08 09:21:33 2018) dymosim started ... "dsin.txt" loading (dymosim input file) Residual component 1 of system 1 is 1.255542e+002 Residual component 2 of system 1 is 1

问题 I'm changing the initial 2 parameter values (over the range of possible values) with pyFMI and simulate the model response I can see that my response is affected only by 1 variable change and not by the other but if I simulate the model only with the second variable (that is not changing in inital simulations) I can clearly see the effect on the model response. model.reset() model=load_fmu('Series_0Resistance.fmu') tstart = model.get_default_experiment_start_time() #### start time of the

问题 I am using Dymola in Linux. Recently I find I need to update the Modelica standard library from 3.2 to 3.2.1(Got from github). Anyone knows what I need to set up such that Dymola starts with Modelica 3.2.1? Thanks a lot 来源： https://stackoverflow.com/questions/23792259/update-modelica-standard-library-in-dymola-in-linux

问题 I'm building a Media-Library in Dymola similar to Helmholtz-Media but for Ammonia+Water, a mixture. You get a lot of not explicitly solvable equations. Because of the structure of the Media and Fluid libraries in Modelica I need to be able to get my thermodynamic state from p, h and x. The state-vector consists of d, T, and x. This is a simple example how to get the state-vector: model getState_phX parameter AbsolutePressure p = 500000 "pressure"; parameter SpecificEnthalpy h = 2500000

问题 I was wondering if there already exists a possibility to extract from flat Modelica code all variables AND their corresponding types (classnames respectively). For example: Given an extract from a flattened Modelica model: constant Integer nSurfaces = 8; constant Integer construction1.nLayers(min = 1.0) = 2 "Number of layers of the construction"; parameter Modelica.SIunits.Length construction1.thickness[construction1.nLayers]= {0.2, 0.1} "Thickness of each construction layer"; Here, the

问题 I can't really find any answer in the Modelica specification so ill ask you guys. The specification states that A tool is free to solve equations, reorder expressions and to not evaluate expressions if their values do not influence the result (e.g. short-circuit evaluation of Boolean expressions). If-statements and if-expressions guarantee that their clauses are only evaluated if the appropriate condition is true, but relational operators generating state or time events will during continuous

问题 Is there a way to change the value of "Maximum number of event iterations" , eviter , that is set to 20 in dymola? 回答1: It seems like dymosim.ini is not used for regular simulations (Note the version in line 4: dymosim.ini states 1.1, whereas the dsin.txt has 1.4 written in Dymola 2019). I also could not find a function or variable in Dymola to change eviter , so the only solution I can think of is to edit dsin.txt before simulation. The code below shows how a function could look like which

问题 I want to do local senstivity analysis in Dymola to evaluate different parameters affecting the energy consumption in a building (for multi-familyhouse). Can anyone give me some suggestions, how to do it in Dymola (Modelica) software? 回答1: You could export you model as FMU and then follow one of many the different paths for sensitivity analysis with FMUs: PyFMI + SAlib Sensitivity Analysis using PyFMI - FMU in for-loop FMI Toolbox for Excel by Modelon http://www.modelon.com/products/modelon

问题 Following this question, I modified my code to: model test // 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 Length r3

问题 Example: You create a model with 9 parameters you expect to be editable in the Simulation tab and user-settable in the FMU. However, Only 5 parameters appear to be editable from the Simulation tab. Likewise, FMU has only 5 user-settable parameters. 回答1: Solution: To generate more efficient code, Dymola sometimes "evaluates" parameters. annotation(Evaluate=false) tells Dymola a parameter should not be evaluated. Example: parameter Real theAnswer = 42.0 "The answer to life,…" annotation