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When trying to show a full circle case, Turbo Post issues an error message similar to the following one:
Operation failed with unrecognized system exception.
An attempt to recover from a previous error has failed.
The application is likely to be in an unstable state.

When taking the same case from Turbo Pre (not entering General Mode) > Solver > into Turbo Post the Turbo Report fails to load and Turbo Post issues an error message similar to the following one:
Failed to initialize component 'Component 1' in
domain 'R1' for conversion type 'Cartesian to Turbo'.
Cannot find turbo variable 'Streamwise Location'.
Turbo mode may not be initialized properly.
Cannot evaluate 'minVal' on 'Streamwise Plot of Pt Line' as it does not have points.

Turbo Pre writes incomplete TURBO POST DATA information when CFX-Pre is restarted in Turbo Mode using a def file.

WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Service Pack 1.

######## WORK NOTES COPIED FROM INCIDENT 599894 ########
**** Entered By: TS319341 @ 03/09/2007 07:56 AM ****


Getting different results for plane13 and plane223
I created a simple structural-thermal static coupled analysis. In the first example a plane 13 is used, in the second one a plane 223. These are identical 2D axisymmetric models of a disk spinning at 200 revolutions per second and at 1000 C above the reference temperature. Material properties are orthotropic but linear. Using orthotropic properties, the results differ substantially (the PLANE223 model is correct). If materials are isotropic, there is no difference in results (both models are correct).

Further testing:

testOrtho_2D_af_13.txt: PLANE13 model
testOrtho_2D_af_223a.txt: PLANE223 model, matrix coupled thermal and structural matrices
testOrtho_2D_af_223b.txt: PLANE223 model, load vector coupled thermal and structural matrices
testOrtho_2D_af_223c.txt: PLANE223 model, load vector coupled thermal and structural matrices with NSUB,2 to force more than one iteration for (hopefully) proper coupling.

As you can see from the attached plots, only the direct coupled method ('223a' files) appears to give sensible results (we expect tensile radial stresses about a third of the way from the center of the disk, NOT negative ones as determined by all the load vector coupled models).


The issue seems to be related to a misinterpretation of the TUNIF functionality. According to the TUNIF command description, its behavior varies depending on whether the analysis is simultaneous or iterative:

"Since TUNIF (or BFUNIF,TEMP) is step-applied in the first iteration, you should use BF, ALL, TEMP, Value to ramp on a uniform temperature load."

In other words, when the analysis is simultaneous (matrix coupling between U and TEMP using keyopt(2)=0 with PLANE223), the temperature nodal load is zero (TUNIF ramped) and

######## WORK NOTES COPIED FROM INCIDENT 599894 ########<br>**** Entered By: TS319341 @ 03/09/2007 07:56 AM ****<br><br><br>QUESTION:<br><br><br>Getting...

Class 3 Error

An incorrect value may be used for the Specific Heat Capacity at Constant Volume.

An unset variable means that the solver may use an incorrect value for Specific Heat Capacity at Constant Volume.
(a) The Specific Heat Capacity at Constant Volume may be set to the same value as for the Specific Heat at Constant Pressure. This is correct for constant density materials, but not for others.
(b) In a multi-phase simulation, if the first fluid in the Fluids List is a constant density material, then the Specific Heat Capacity at Constant Volume may be incorrect for second and subse

WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Service Pack 1.

For multi component cases, the mass flow value per passage is reset to zero when going from the physics panel to the Boundary conditions panel in the Turbo Pre wizard.

When the code couldn't determine the number of passage in 360 correctly, the mass flow is reset to zero.

WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Service Pack 1.

I am interested in how the Herschel-Bulkley model works in CFX. When I do the calculations by hand, I have to explicitly find the yield surface in the fluid then divide my region into two pieces for the velocity calculations. How does CFX calculate the yield surface, if at all? The Herschel-Bulkley equation gives an infinite viscosity for parts of the flow. Having an infinite viscosity would give numerical problems, so what modifications to the Herschel-Bulkley equations have been made to make the numerical solution tractable? How are the material parameters, yield stress and min/max shear strain rate values, used?

<br><br>The shear rates are clipped using the minimum and maximum shear rate parameters. The solver then calculates a viscosity based on these clipped values. This ensures that the...

Is it possible to use Ansys 10 or 11 on Linux Redhat Enterprise 5 OS.
If not, when will Redhat Enterprise 5.0 be tested/certified?

As of May 15, 2007:<br><br>We have not tested or certified ANSYS 10.0 or 11.0 on Redhat Enterprise 5.0, as of today.<br>We can not say if ANSYS 10.0/11.0 will run on RH 5.0 with...

I want to calculating Lorentz force based upon my own user-modified B field for subsequent use in structural analysis ' I need a procedure for a "manual" LDREAD,FORC. Do you have an example demonstrating such a procedure?

If you need to obtain Lorentz forces using a modified value of B superimposed on that which is calculated by modeled current sources, I think you will need to perform a cross product using element...

Customer installed ANSYS Workbench x64 version 11.0 on his computer.
While installing, he is getting a message saying that it could not register " winx64 dockingpane.Unicode.ocx ".
When he tries to open Workbench after installing the software, he is getting Microsoft Visual C++ run time error message.

What causes this and what is the fix?

For some reason unknown to us, the operating system would not allow us to copy the<br>MFC71U.DLL file to the system32 directory.<br><br>Copy the following file to the...

A Linux 64 bit machine (local machine) is connected to a windows machine through Samba. While trying to remotely run CFX Solver on the Windows machine through Samba, the error message below appeared. How can this problem be resolved?

Error copying MMS input file mms for reading: Operation not supported.

Symlinks will not work over Samba. The code expects this and checks for an ¿Operation not permitted¿ error. If it finds this, it falls back to copying the file. The workaround is to...

The borrowing feature will only allow borrowing for up to one week.
Is it possible to allow administrative extensions of this?

No, This is by design.<br>Academic Products have a 1 week limit borrow time.<br><br>Looking at the license file you will see the word "Borrow". If it does not have...

The solver can give obviously incorrect values for heat transfer in multiphase and particle transport calculations, as the latent heat is wrongly calculated.

The values for reference enthalpy and reference entropy of H2Ol are incorrectly specified to be consistent with values for H2O where the specific heat is specified as a NASA polynomial. As well as some of the default materials files, this also applies to the evaporating_drops and spray_dryer templates.

WORKAROUND:<br>If such a multiphase or particle transport calculation is undertaken, set the reference enthalpy and perhaps reference entropy to more appropraite...

Class 3 Error

The values of turbulence variables at an inlet may be incorrectly calculated in an inhomogeneous multi-phase simulation, if the turbulence itself is calculated as homogeneous.

The code calculates the turbulence values from the velocity of just the first phase, rather than a volume fraction weighted average of both phases, so there is no problem if both phases are given the same velocity at

WORKAROUND:<br>If it is necessary for the phases to have different velocity values, set the turbulence values explicitly.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0.

I am trying to perform a CFX-DesignXplorer study. I have defined the parameters for my study
and have defined the definition, case, cmdb, and Post state file for the run. When I try to start
DesignXplorer. though, I just get a blank DX screen, The icons which you nrmally use to set the parameter
ranges, etc, are missing. I've tried restarting the simulation, recreating it, and rebooting my computer
but nothing helps. What can I do?

<br><br>This sometimes happens when the file that sets the window layout gets corrupted.<br><br>There are a couple of things you can try:<br><br>First, from...

CFX-Mesh 11.0 saves the generated mesh in the CMDB file. The mesh information may increase the file size enormously. How can I keep the mesh settings and geometry separate and save the mesh only in the GTM file?

In CFX-Mesh, open the menu 'Tools / Options...'. Go to 'Meshing /CFX-Mesh Options'.<br> Under 'Volume Mesh', set the 'Volume Mesh...

Customer gets the following error message while relinking an ansys executable.

/ansys_inc/v110/ansys/customize/user/aix64/ibm_dgem.o not found

Why is he getting this error?

This file was excluded from the IBM AIX 11.0 release.<br>Place the attached file in the following directory:<br><br>/ansys_inc/v110/ansys/customize/user/aix64/

What is the treatment of periodic boundary conditions for radiation in ANSYS CFX?

<br><br>Radiation periodicity is very similar to fluid flow depending on how you treat it numerically. By default, we treat periodic domain interfaces (translational and rotational) as...

Does CFX and CFX parallel computing work on Microsoft Compute Cluster Server?

Currently CFX 11 is not fully supported on Windows CCS [Windows Server 2003 with the Compute Cluster Pack].<br>It may work fine but it will not use any of the CCS specific components (Job...

Is there a way to set up a plane so its origin is located at the center of a hole?

Yes, there are two methods of doing this. See accompanying files attached to this solution for an example.<br><br>Method 1: After importing the solid with hole into DesignModeler (DM),...

Where can I get information and how-to on ANSYS License Borrowing?

Please refer to the ANSYS 11.0 Licensing Guide, chapter 5.6. The guide should come as a hardcopy together with your ANSYS 11.0 Distribution and is available for download from the ANSYS Customer...

Definition of viscous and pressure forces, computation of force components in CFX Post?

<br><br>From theory, shear stress is a symmetric tensor<br><br>T_xx T_xy T_xz<br><br>T_yx T_yy T_yz<br><br>T_zx T_zy...

Do you have any examples of the LS-DYNA *MAT_WINFRITH_CONCRETE_REINFORCEMENT material model?

Yes, please see the attached LS-DYNA keyword ASCII input file. Although this model is not supported by<br> ANSYS LS-DYNA, you can edit the .K file generated by the interface and run the...

Class 3 Error

When using the Small Droplet Temperature model, the interphase heat transfer is not correctly predicted wherever the liquid droplets have not reached equilibrium.

For multiphase flow calculations with dispersed phases using the small droplet temperature model, the interphase heat transfer incorrectly uses the local saturation temperature for the droplet/vapor interface condition. This means that the gas phase total enthalpies are not quite right because the heat transfer rate is not correctly predicted in parts of the flow where the liquid droplets have not reached equilibrium. The correct approach is to use the droplet internal temperature to set the interface condition, which is specified algebraically under small droplet

WORKAROUND:<br>No workaround is current available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Service Pack 1.

When perfoming a volume/density calculation using the Redlich Kwong model, a sudden density discontinuity can happen leading to a solver crashing.

The initial guess for the newton root finder is based on the ideal gas equation. The initial guess will be returned at any given temperature when the ideal gas equation of state predicts a volume less (or higher density) than that of the Redlich Kwong equation.

WORKAROUND:<br>No workaround is current available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Service Pack 1.

Do you have a model and/or input file demonstrating a procedure to model a hypothetical dual beam MEMS filter such as the one described below?


Two fixed-fixed MEMS beams are lightly tethered by a spring. A time varying signal applied to an electrode under the first causes it to oscillate up and down. The spring transmits a mechanical 'signal' from this first beam to second one. When the second one vibrates, it induces an electrical signal in an electrode beneath it because it is maintained at a constant DC potential (the oscillation of the second beam varies the capacitance between it and the electrode, so the constant voltage applied to one of the plates of what is in effect a time varying capacitor generates an output signal).

Since the signal is efficiently passed in this manner only at resonance (beam natural frequency), the device functions as a filter (other frequencies aren't passed).

Both beams have a DC potential (bias voltage) applied to them during operation. This serves to partially pull them down. The resulting prestressed condition alters beam natural frequency. The DC bias is adjustable, so the frequency that the filter passes is adjustable as well ' by design.

A significant aspect of the operation of this device is the fact that the amplitude of the output signal is significantly affected by the electrical load (RLC) that the output electrode under the second beam drives. Circuit coupling is desired to account for this bi-directional coupling in a simulation.


I want to simulate operation (frequency response) of this device including the effects of all aforementioned features. First and foremost, an xy plot of output voltage versus frequency is desired. ROM144 approach is somewhat preferred due to its ability to account for field fringing, but TRANS126 is entirely acceptable.

Please inspect the attached presentation and review the procedure embodied inthe attached parameterized input files. TRANS126 is used between a section of each of the beams at midspan and the...

Class 3 Error

The heat transferred from one solid to another across a GGI interface is too low when the problem has radiation.

For cases including thermal radiation through a solid domain (participating, or surface to surface), the radiative heat flux term boundary closure in the energy equation is missing for Solid-Solid Domain Interfaces with Mesh Connection = GGI. The solution is incorrect as the amount of heat crossing the domain interface only accounts for the conduction h

WORKAROUND:<br>No workaround is current available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Service Pack 1.