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Active Contributor
Sultan9009
Posts: 34
Registered: ‎06-19-2012

Help with multiphysics

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06-19-2012 05:47 PM

Hi I am Asif

I need help simulating, fluid flow through a porous medium. I created a solid cylinder in inventor with a inlet and outlet. The fluid I want to use to perform the simulation is air. I want to find the pressure on the porous medium, with a velocity of 20cm/min coming out the outlet. I having problems trying to simulate this scenario. I look at the tutorials provided, but it does not help. Can you please assist me with this task.

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Employee
Joey.X
Posts: 259
Registered: ‎06-14-2010

Re: Help with multiphysics

06-20-2012 08:23 AM in reply to: Sultan9009

 

Hi, Sultan9009

Here are steps for flow through porous media (combination of porous parts and regular fluid parts). 

- In CAD modeling, set the porous material as part(or multiple parts), and push the CAD into simulation. Or read CAD assembly from SIMMP. 

- In SIMMP/FEDEditor/tree view, select porous part(s), select element definition, under "general", change Viscosity model to "Porous media model"; under Orientation, set material model as Isotropic or Orthotropic, for orthotropic, the material axis etc. need to be specified. 

-  In SIMMP/FEDEditor/tree view/porous part(s), right click Material, define porous material properties such as permeability, inertial coefficient etc. 

Attached is a simple 2D planar model for your reference.



Jianhui Xie, Ph.D
Principal Engineer
MFG-Digital Simulation
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Active Contributor
Sultan9009
Posts: 34
Registered: ‎06-19-2012

Re: Help with multiphysics

06-20-2012 11:11 AM in reply to: Joey.X

Autodesk (R) Simulation Steady Fluid Flow

Version 2012.00.00.0163-W64/X64 04-Mar-2011

Copyright (c) 2011, Autodesk, Inc. All rights reserved.

 

 ----------------------------------------------------------------

    Date & Time         : 06-20-2012  14:01:54

    Input File          : E:\Reactor.ds_data\4\ds        

    Command Line Options: -silent-x721724

 

    PROGRAM               VERSION: 201200000163

    Alg-win-x64.DLL       VERSION: 201200000163

    AlgConfig-win-x64.DLL VERSION: 201200000163

    Agsdb_ar-win-x64.DLL  VERSION: 201200000163

    AlgSolve.exe          VERSION: 201200000163

 ----------------------------------------------------------------

 **** Starting main program

 

 **** Model Unit System Settings:

      --------------------------------------------

       Unit System              : English (in)

       Force                    : lbf

       Length                   : in

       Time                     : s

       Temperature (Absolute)   : deg F (R)

       Thermal Energy           : in*lbf

       Voltage                  : V

       Current                  : A

       Electrical Resistance    : ohm

       Mass                     : lbf*s^2/in

      --------------------------------------------

 

 

 **** Memory dynamically allocated = 31042 KB (1% of physical memory)

 

 **** Generating coordinates

 **** Generating initial conditions

 **** Generating boundary conditions

 

 **** FEA information

      Model Dimension........................... =   3D model

      The number of nodes....................... =   18650

      The number of elements.................... =   56266

      The number of equations................... =   69384

 

 **** Segregated Scheme Data

      Select segregated scheme ................. =   T

      Solver for momentum equations ............ =   Automatic          

      Solver for pressure equations ............ =   Automatic          

      Velocity relaxation factor ............... =   7.000E-01

      Pressure relaxation factor ............... =   5.000E-01

      Inertial relaxation factor ............... =   1.000E+00

      Apply automatic adaptive parameter control =   T

      ID of Detect stagnation due to oscillation =   1

 

      The number of equations (U)............... =   16999

      The number of equations (V)............... =   16999

      The number of equations (W)............... =   16866

      The number of equations (P)............... =   18520

 

 

 **** Turbulence Model Data..................... =   Off

 

 **** Proceeding with Equal-Order Segregated Method

 **** ENTERING TIME LOOP

 

 Step                                        NonL. Solv. == Euclid L-2 Norm ==

 Intv  Step     Time   Percent    DT      L  Iter  Iter   R_Norm_V    R_Norm_P

    1     1  1.000E+00   0.00  1.000E+00  1          50   |R/F|u =  NaN     

 **** Error: Divergence detected in iterative solver.

             Please try sparse solver.

Can you help me with this error?

 

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Employee
Joey.X
Posts: 259
Registered: ‎06-14-2010

Re: Help with multiphysics

06-20-2012 11:44 AM in reply to: Sultan9009

This error most probally came from improper model setting such as boundary conditions, could you share your model setups and mesh info? 

You can also try sparse equation solver which is more robust bet less speedy than default iterative solver. 

change it from parameters icon/solution/Formulation>>/segregated control/solver control/change "iterative" (2 entries) to BCSLIB-EXT. 

Jianhui Xie, Ph.D
Principal Engineer
MFG-Digital Simulation
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Active Contributor
Sultan9009
Posts: 34
Registered: ‎06-19-2012

Re: Help with multiphysics

06-20-2012 12:06 PM in reply to: Joey.X

May I get your email because the file is too big to be posted?

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Employee
Joey.X
Posts: 259
Registered: ‎06-14-2010

Re: Help with multiphysics

06-20-2012 12:18 PM in reply to: Sultan9009

Could you put the whole archive model in dropbox or skydrive etc and share to my email?  

my email: xjohnh@gmail.com   

Jianhui Xie, Ph.D
Principal Engineer
MFG-Digital Simulation
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Active Contributor
Sultan9009
Posts: 34
Registered: ‎06-19-2012

Re: Help with multiphysics

06-20-2012 12:22 PM in reply to: Joey.X

I shared the model on dropbox

 

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Employee
Joey.X
Posts: 259
Registered: ‎06-14-2010

Re: Help with multiphysics

06-20-2012 12:33 PM in reply to: Sultan9009

have a quick look, the outlet surface can't have ioBC and pressure BC simultaneously, suggest to get rid of pressure BC and try it again. 

Jianhui Xie, Ph.D
Principal Engineer
MFG-Digital Simulation
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Active Contributor
Sultan9009
Posts: 34
Registered: ‎06-19-2012

Re: Help with multiphysics

06-20-2012 12:38 PM in reply to: Joey.X

I am not sure of how to get rid of pressure B. Can you tell me how?

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Employee
Joey.X
Posts: 259
Registered: ‎06-14-2010

Re: Help with multiphysics

06-20-2012 12:43 PM in reply to: Joey.X

At design scenario 4, the model has veolcity BC at inlet surface,  inlet/out BC and pressure BC at outlet surface. the latter is redundant. It is suggested to delete pressure/traction BC by click "loads and constriant group", select pressure BC, right click to delete. 

Jianhui Xie, Ph.D
Principal Engineer
MFG-Digital Simulation
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