I sometimes encounter singularity errors that I have difficulties to trace.
1) what does exactly mean singularity errors in Modelica?
2) Can anyone advise me on good practices and tips that can help to trace and correct singularity errors?

I think, the problem may be from the WasteWater package. Because, I run another model on OM 1.9.3 and it did work without problem.

However, I noticed the the omc of 193 does not keep the parenthesis '() within mathematical operations.  Why?  Because, this might be risky to get the right output.  The parenthesis give more control to aretemetic operations order.

Thanks Adrian,

I tried to load Wastewater 2.1.0 on OpenModelica 1.9.3, Windows 7  64bit.  It still failed to open it.  I see the following error message:

[1] 10:41:13 Syntax Warning
[F:/WasteWater/WasteWater-2.1.0/WasteWater-2.1.0/WasteWater 2.0.1/ASM2d/package.mo: 202:14-202:79]: The file was not encoded in UTF-8:
  "Concentration of effective substance in precipitant flow   [g/m?]".
  Defaulting to 7-bit ASCII with unknown characters replaced by '?'.
  To change encoding when loading a file: loadFile(encoding="ISO-XXXX-YY").
  To change it in a package: add a file package.encoding at the top-level.
  Note: The Modelica Language Specification only allows files encoded in UTF-8.

[2] 10:41:13 Grammar Warning
[F:\WasteWater\WasteWater-2.1.0\WasteWater-2.1.0\/WasteWater 2.0.1/ASM1/package.order: 0:0-0:0]: The package.order file does not list all .mo files and directories (containing package.mo) present in its directory.
Missing names are:
        Preclar

[3] 10:41:13 Grammar Error
[F:/WasteWater/WasteWater-2.1.0/WasteWater-2.1.0/WasteWater 2.0.1/ASM1/Preclar.mo: 1:1-477:12]: Expected the package to have name Preclar, but got PreClar.

[4] 10:41:13 Scripting Error
Failed to load package WasteWater (2.0.1) using MODELICAPATH F:\MODELICA\WasteWater\WasteWater-2.1.0\WasteWater-2.1.0\;C:/OpenModelica1.9.3Nightly/lib/omlibrary.

Ok, I will post specific error messages that I noticed

I meant 2.1.0.  Both OM 190 and 192 are not loading it. I am on Windows 7 64 bit

Open Modelica is unable to load WasteWater2.0.1

Has anyone tried it and can let me know how to run it?

I tried to run some codes in OM 192 but gest errors very often. Surprisingly, OM 190 works for most of the codes which were not run using OM 192.

Has anyone noticed that or there are a different modeling instruction after 190?

Is this forum still active ?

I did hard coding through local declaration.  It does work anyway.

Hello everyone,

I have two connectors with the same declaration; i.e one flow and one potential variables

Connector1
flow SI.MassFlowRate Qm;
        SI.Pressure p;
End Connector1;


Connector2
flow SI.MassFlowRate Qm;
        SI.Pressure p;
End Connector2


Except the name of the connectors (connector1 as incoming and connector2 as leaving flow), the rest is the same in both cases.

Since the flow is reversing while simulating, despite I followed the signe convention (sume of in and out is zero), I tried also using input and output for the flow in each connector. The flow still reversing at some junctions.

Can anyone help me what I should consider in this situation?
PS: I am in the learning curve to apply modelica for a real project.

Thanks

Hi There,

I am trying to construct a Modelica model with component connectors. But when I try to run, I exprieneced the following execution failure:

The following variables are iteration variables of the initialization problem:
cv.cPort_b1[1].Qm
cv.cPort_b1[2].Qm
cv.cPort_b1[3].Qm
but they are not given any explicit start values. Zero will be used.

I tried to initiate with the following declaration but it  it appears that it is not the correct syntax:
cv.cPort_m1[3](start=10,10,10)

If I have to initiate them, can anyone let me know how to do that?

Thanks