How can I stop the solver gracefully from user Fortran in a steady state run? |
Create an 'stp' file in the run directory from user Fortran. A complete working<br>example is provided, which demonstrates this method. See attached zip archive<br>file... |
How can I stop the solver gracefully from user Fortran in a transient run? |
Set the logical data area /FLOW/ALGORITHM/CONTROL/NEXT_TSTEP to FALSE from<br>user Fortran. A complete working example is provided, which demonstrates this<br>method. See attached zip... |
Q. How does one specify a swirl velocity component at a CFX Inlet?
A.
To specify swirl at an inlet, one can make a local cylindrical coordinate system with its center at the center of the inlet. The Z axis of this coordinate system should be normal to the boundary surface. In the basic settings of the inlet, make sure of the reference to this new coordinate system. Then in boundary details, the velocity component in the Z direction will determine the mass flow. The radial component will most likely be zero.
Create an expression for the azimuthal (theta) component if the swirl velocity is a function of the distance from the center of the inlet. This will use the variable "r" which is measured from the Axial direction (the Z axis) in the new coordinate system.
The setup provides additional flexibility in setting the axes. Therefore one must, in Analysis Details, go to the Axis Definition and as the option choose Coordinate system. For the Rotation axis choose the third direction (i.e. "Coord 1.3"). |
Q. How does one specify a swirl velocity component at a CFX Inlet?<br><br>A.<br><br>To specify swirl at an inlet, one can make a local cylindrical coordinate system with... |
Do you have any examples of a foam bumper impact simulation? |
Yes, please see the fully commented ANSYS LS-DYNA 11.0 model that is<br> attached to this record. A rigid steel block representing a car impacts a<br> truncated pyramid... |
Why does a modal analysis with a point mass solve in WB Simulation 10.0, but exit with a memory error in v11.0? |
The reason why it solves in V10 and not V11: CE's are not the issue. They are the same in both versions. In V10, when you do a modal analysis using the WB "iterative"... |
SYMPTOM:
When using the report functionality of CFX Post, the names of chemical species (such as CH4) which should be in upper case are written in lower case (ch4).
PROBLEM:
This is due to incorrect parsing of these names. |
WORKAROUND:<br>There is no workaround.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
Class 3 Error
SYMPTOM:
Incorrect pressure and temperature fields can be obtained in transient moving mesh calculations that use the total energy formulation.
PROBLEM:
This is caused by a conflict in the discretisations of the dp/dt and pressure advection terms in the total energy equation. These terms, which almost balance each other in the equation, need to be discretised in a si |
WORKAROUND:<br>There is no workaround.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
Class 3 Error
SYMPTOM:
Incorrect answers are obtained for cases using the alternate rotation model which have boundary conditions for stationary frame velocity components.
PROBLEM:
This is caused by the software incorrectly converting the velocity components into the rot |
WORKAROUND:<br>If possible, run without the alternate rotation model.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
Class 3 Error
SYMPTOM:
If a user surface is imported into CFX Post for a particle transport model calculation, and the surface is then used for evaluating expressions involving particle mass flow rates, then the computed answers are incorrect.
PROBLEM:
This is caused by the software not knowing any integration point information for the user surface and then injudiciously trying to calculate mass flows from the density and velocity, but using the fluid rather than parti |
WORKAROUND:<br>Restrict mass flow calculations to boundaries, or locators created in CFX Post.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
How can I define material properties that depend on solution variables in CFX 11.0? |
A user may define material properties that depend on solution variables (e.g. Temperature) by defining a user fuction or a polynomial:<br><br>FUNCTION: sh_pol<br> Option =... |
SYMPTOM:
A chart with multiple chart lines takes a long time to create because every time a chart line is added, CFX-Post re-reads all of the transient files to extract the relevant data.
PROBLEM:
CFX-Post doesn't allow the definition of multiple chart lines at once, and doesn't give the user any control over when it should re-read the transient data (which can take a long time if the run has a large number of timesteps. |
WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1. For this update, a "Refresh" button has been added... |
SYMPTOM:
The CFX Solver fails if a region locator is used in a callback (e.g. minVal(Pressure)@REGION:myregion) when the simulation includes mesh deformation. The error is of the form:
Details of error:-
----------------
Error detected by routine MAKDAT
CDANAM = AREA CDTYPE = REAL ISIZE = 1
CRESLT = OLD
Current Directory : /FLOW/GEOMETRY/REG1
PROBLEM:
This is due to a small error in the coding of this functionality. |
WORKAROUND:<br>There is no workaround.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
SYMPTOM:
Incorrect values of laminar burning velocity can be obtained from the Solver for certain conditions. This will lead to either a discontinuity of the burning velocity, which can be observed in CFX Post, or to blow-out of the flame.
PROBLEM:
There are errors in the coding for equivalence ratios that are inside the 'Flammability Limits' and outside the 'Fit Range'. The following options are affected by the issue: the "Metghalchi and Keck" option for Laminar Burning Velocity and the "Quadratic Decay" and "Fifth Order Polynomial" options for Equivalence Ratio Correlation/Reference Burning Velocity. |
WORKAROUND:<br>Either specify the Laminar Burning Velocity in CEL or use the "Beta Function" option for Equivalence Ratio Correlation/Reference Burning... |
In Workbench 11.0 on Windows XP x64, after generating a mesh in WB Meshing, there is no "Proceed to AUTODYN" Workbench task on the Project page. How do I transfer a mesh from WB Meshing to AUTODYN 11.0 on Windows XP x64? |
AUTODYN 11.0 on Windows XP x64 is not formally released yet (beta status). When it is officially released/supported, there should be a direct "Proceed to AUTODYN" WB task to... |
Are there any COMBIN40 examples with the FSLIDE and GAP features used? |
Yes, please see the attached ANSYS 11.0 Classic example.<br><br><br><br><br>.
|
What is the y+ requirement for Spalart Allmaras model in CFX? |
There are two wall treatment options in CFX solver, which are similar to those in fluent:<br><br>1: If the user chooses Default, it means the grid is a low-Reynolds number grid, then... |
The real constant input for unsymmetric MATRIX27 has changed at 11.0.
At release 10.0 and prior, MATRIX27 allowed for unsymmetric matrix input when KEYOPT(2)=1. At release 11.0, this option has become undocumented, and unsymmetric matrix input is specified with KEYOPT(2)=2. (There is also an additional KEYOPT(2)=3 for skew symmetric matrix input that is introduced at 11.0.)
The ASCII table below provides a visual comparison of the differences in real constant input between 10.0 and 11.0 and may help serve as a mapping guide for changing 10.0 input to 11.0 input.
ANSYS 10.0 and prior (KEYOPT(2)=1):
001 002 003 004 005 006 | 007 008 009 010 011 012
079 013 014 015 016 017 | 018 019 020 021 022 023
080 081 024 025 026 027 | 028 029 030 031 032 033
082 083 084 034 035 036 | 037 038 039 040 041 042
085 086 087 088 043 044 | 045 046 047 048 049 050
089 090 091 092 093 051 | 052 053 054 055 056 057
------------------------+------------------------
094 095 096 097 098 099 | 058 059 060 061 062 063
100 101 102 103 104 105 | 106 064 065 066 067 068
107 108 109 110 111 112 | 113 114 069 070 071 072
115 116 117 118 119 120 | 121 122 123 073 074 075
124 125 126 127 128 129 | 130 131 132 133 076 077
134 135 136 137 138 139 | 140 141 142 143 144 078
ANSYS 11.0 (KEYOPT(2)=2):
001 002 003 004 005 006 | 007 008 009 010 011 012
013 014 015 016 017 018 | 019 020 021 022 023 024
025 026 027 028 029 030 | 031 032 033 034 035 036
037 038 039 040 041 042 | 043 044 045 046 047 048
049 050 051 052 053 054 | 055 056 057 058 059 048
061 062 063 064 065 066 | 067 068 069 070 071 072
------------------------+------------------------
073 074 075 076 077 078 | 079 080 081 082 083 084
085 086 087 088 089 090 | 091 092 093 094 095 096
097 098 099 100 101 102 | 103 104 105 106 107 108
109 110 111 112 113 114 | 115 116 117 118 119 120
121 122 123 124 125 126 | 127 128 129 130 131 132
133 134 135 136 137 138 | 139 140 141 142 143 144 |
The real constant input for unsymmetric MATRIX27 has changed at 11.0.<br><br>At release 10.0 and prior, MATRIX27 allowed for unsymmetric matrix input when KEYOPT(2)=1. At release... |
SYMPTOM:
When Loading a machine report for a case with multiple passages in one component, CFX-Post issues an error message similar to the following one:
=================================================================
ERROR
CCL validation failed with message:
Error: Parameter /DOMAIN:R1/Number of Passages in 360 = 9.99999 must be type Intege
=================================================================
PROBLEM:
There is a bug when CFX-Post calculates the number of blade passages in 360 based on the parameter "Number of Components in 360". Instead, CFX-post should use the parameter "Number of Passages in 360" from TURBO DATA which gives the exact number of blade passages. |
WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
Does CFX use modified pressure in the code? If yes, how can I change it? |
<br>In CFX-Pre, Solver and Post the Static Pressure or Total Pressure always includes the turbulence contribution term 2/3*rho*k by default for k-epsilon/k-omega based turbulence models;... |
SYMPTOM:
For some high wrap cases, when a layer is manually added, it is placed very close to the shroud.
PROBLEM:
The algorithm in ICEM for the surface reparametrization used an arc length based method which misplaces the manually added layer. |
WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
SYMPTOM:
When Float leading and trailing edge vertices on blade is enabled, a folded mesh can be obtained for high twisted blades.
PROBLEM:
Parameterization of two surfaces adjacent to leading or trailing edge may not have the same parameterization from hub to shroud. |
WORKAROUND:<br>Suing streamwise lofting of blade or<br>Mesh Generation parameter set to Constant Span or<br>Moving the leading and trailing points (geometry) and mesh with Float... |
SYMPTOM:
For some blade geometries (blades with cut off), when generating the O-grid mesh, one side of the O-Grid is folded inside the blade profile, while the other side is OK
PROBLEM:
There is a bug when generating the O-grid for a blade which the suction and pressure sides are not parallel. |
WORKAROUND:<br>Make the O-grid bigger or<br>Move the outlet block closer to the blade trailing edge.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
SYMPTOM:
For a splitter configuration with around 360 degrees of wrap, the topology doesn't look right when it is created.
PROBLEM:
Theta is not being computed properly in the area where it changed by more than 180 degrees. |
WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 11.0 Update 1.
|
Why does ICEBOARD 11.0 produce missing DLL error unless TASPCB is installed?
--------------------------------------------------------------
DETAILS:
Customer reports that he gets a missing dll error when he tries to solve in ICEBOARD 11.0. On another PC that had TASPCB 10.0 installed there was no error. Customer installed TASPCB 10.0 on the first PC and then the dll error went away.
--------------------------------------------------------------
ERROR MESSAGE RECEIVED:
All the error message says is, "Missing dll". |
In the first release of V11 of Iceboard, an incorrect mesher dll was included. The Iceboard installation now on the customer portal has this corrected. If there was already an installation of... |
ANS_ADMIN->Configuration Options->Configure Cluster is not accessible on Windows x64. The menu is greyed. Why? |
This is a defect that will be fixed in ANSYS 11.0 Service Pack 1. The workaround is to either create the file on a 32bit Windows machine and copy it over<br>to the x64 machine or create the... |