Community Computational Fluid Dynamics OpenLabs Problems with openLabs

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Problems with openLabs

sriluta

Hey,

iam using OpenLabs because my inlet boundary conditions change with the time and the azimuth angle in the unsteady Simulation.  So OpenLabs works with SI Units. In the first time, I defined the pressure in bar ( since didn't know that OpenLabs works with SI Units and there the pressure is defined in pascal ). So with the following function implemented in OpenLabs  for the absolut total pressure I didn't got Problems: 

 3.853 + (-0.9863)*cos(tCoord*1.966 + 2*PI*Time/timePeriod) + 0.08183*sin(tCoord*1.966+ 2*PI*Time/timePeriod) + (-0.2735)*cos(tCoord*3.932+ 2*PI*Time/timePeriod) + 0.6356*sin(tCoord*3.932+ 2*PI*Time/timePeriod) + 0.588*cos(tCoord*5.88 + 2*PI*Time/timePeriod) + (-0.1489)*sin(tCoord*5.88 + 2*PI*Time/timePeriod) + (-0.07768)*cos(tCoord*7.864 + 2*PI*Time/timePeriod) + (-0.2232)*sin(tCoord*7.864 + 2*PI*Time/timePeriod) + (-0.3242)*cos(tCoord*9.83 + 2*PI*Time/timePeriod) + 0.01536*sin(tCoord*9.83 + 2*PI*Time/timePeriod) + 0.1678*cos(tCoord*11.796+ 2*PI*Time/timePeriod) + 0.2214*sin(tCoord*11.796 + 2*PI*Time/timePeriod) + 0.1408*cos(tCoord*13.762 + 2*PI*Time/timePeriod) + (-0.0754)*sin(tCoord*13.762+ 2*PI*Time/timePeriod) + (-0.1216)*cos(tCoord*15.728 + 2*PI*Time/timePeriod) + (-0.1922)*sin(tCoord*15.728 + 2*PI*Time/timePeriod)

when I found out that OpenLabs works in SI units, I converted the sizes from bar to pascal and created the new following function: 

390101.438+ (−99956.492)*cos(1.963*tCoord + 2*PI*Time/timePeriod)+ 9062.116*sin(1.963*tCoord + 2*PI*Time/timePeriod)+ (−26626.657)*cos(3.927*tCoord + 2*PI*Time/timePeriod)+63969.754*sin(3.927*tCoord + 2*PI*Time/timePeriod)+57284.906*cos(5.890*tCoord + 2*PI*Time/timePeriod) + (−15828.864)*sin(5.890*tCoord + 2*PI*Time/timePeriod) + (−8525.752)*cos(7.854*tCoord + 2*PI*Time/timePeriod) + (−21014.003)*sin(7.854*tCoord + 2*PI*Time/timePeriod) + (−30331.247)*cos(9.817*tCoord + 2*PI*Time/timePeriod)+2857.566*sin(9.817*tCoord + 2*PI*Time/timePeriod)+15956.411*cos(11.781*tCoord + 2*PI*Time/timePeriod)+19562.181*sin(11.781*tCoord + 2*PI*Time/timePeriod)+11641.815*cos(13.744*tCoord + 2*PI*Time/timePeriod) + (−6956.443)*sin(13.744*tCoord + 2*PI*Time/timePeriod) + (−10933.721)*cos(15.708*tCoord + 2*PI*Time/timePeriod) + (−14834.89)*sin(15.708*tCoord + 2*PI*Time/timePeriod). 

If I click in OpenLabs at validate labs everything is fine, if I start the Simulation, the Simulation stops from beginning and say there is a problem with OpenLabs. I also defined the functions for the absolut Total Temperature and arctg( Vt/Vz) and there are no Problems but just with the pressure. Now I dont know what to do,

greetings Slight smile

  • 0

    maybe I how to work with the pow command ?  So If I  want to  transform the first function from bar to pascal in OpenLabs, I think I have to write it in this way:  

    pow(( 3.853 + (-0.9863)*cos(tCoord*1.966 + 2*PI*Time/timePeriod) + 0.08183*sin(tCoord*1.966+ 2*PI*Time/timePeriod) + (-0.2735)*cos(tCoord*3.932+ 2*PI*Time/timePeriod) + 0.6356*sin(tCoord*3.932+ 2*PI*Time/timePeriod) + 0.588*cos(tCoord*5.88 + 2*PI*Time/timePeriod) + (-0.1489)*sin(tCoord*5.88 + 2*PI*Time/timePeriod) + (-0.07768)*cos(tCoord*7.864 + 2*PI*Time/timePeriod) + (-0.2232)*sin(tCoord*7.864 + 2*PI*Time/timePeriod) + (-0.3242)*cos(tCoord*9.83 + 2*PI*Time/timePeriod) + 0.01536*sin(tCoord*9.83 + 2*PI*Time/timePeriod) + 0.1678*cos(tCoord*11.796+ 2*PI*Time/timePeriod) + 0.2214*sin(tCoord*11.796 + 2*PI*Time/timePeriod) + 0.1408*cos(tCoord*13.762 + 2*PI*Time/timePeriod) + (-0.0754)*sin(tCoord*13.762+ 2*PI*Time/timePeriod) + (-0.1216)*cos(tCoord*15.728 + 2*PI*Time/timePeriod) + (-0.1922)*sin(tCoord*15.728 + 2*PI*Time/timePeriod)),1e5) ?

  • 0 in reply to sriluta

    Note from a moderator (can't answer the technical question because it's not my field) - the issue with this being caught as potential spam is because of the repeated text. Clearly it's not spam, but that's a common feature of spam, I'm afraid.

    Andrew

  • 0

    Hi

    The expression in Pascal is correct except that "." needs to be removed from the end of the line.

    If that does not work, we need more information:

    Which version are you using? Fidelity 2022.2?

    On which OS version are you running?

    If Linux: which gcc version?

    Please confirm whether you are using line breaks and if so that they are used consistently? Or did you put all in one line?

    What exactly is the error message? Is there more detail in the log?

    Best regards,
    Colinda

  • 0 in reply to Colinda

    Hey, thx for your response. Yes, the . in the end is also removed. Iam working with Omnis 5.2 and the OS is windows 10. There are no line breaks, put the whole function in one line. So if I start the Simulation I get the following error: 

    "The Simulation Simulation 1 has been stopped: an error occurred during the computation. OpenLabs Error" 

    the log file:

    - OpenLabs Module is activated

    - OPENLABS ERROR: OpenLabs is active for block 0 but the library ..../domain_100000000055232.dll) does not exist, exciting . . .

    - info : [NIMPI : : mpiAbort] OPENLABS ERROR.

    So what I have now done to avoid the error message, is used the first expression which are defined in bar,  put the whole function in mathematical brackets and multiplicate the function with *100.000,  also: (3.853 + ...........))*100.000 and now I dont get an error anymore. 

    Another question would be is there a limit in the Number of characters in the function in OpenLabs ? So I if use up to 15 Terms for the function of the fourier series everything Is fine,  if I want to use 20 terms and more,  the simulation is stopped right at the beginning. 

                   

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