Thank you for everyone's support. I was using the TDMA solver which specifies tight convergence criteria. I read slover guide and found that the PBCGM solver is the suitable solver for the unsymmetric conjugate gradient situtation and turbulence conditions where initial gradients are high. So...
Thank you for your response. The flow is turbulent. I have tried changing the CFD solvers as well. I am sure that the reason the CG method fails is due to iterations don't converge. Only if I could find out how to untight the convergence criteria. I am playing with the relaxing parameters...
So nobody faced this ever before. The error message is not even documented in the ANSYS TROUBLESHOOTING GUIDE. I know it has to do something with convergence crieteria, I tried relaxing convergence criteria but it is giving me the same error. Any suggestions?
Hello guys,
I am trying to run the cfd-thermal analysis. My model was working fine until, I changed the specific heat of the fluid and I started getting this error message.
"Unsymmetric CG method failed catastrophically"
I checked all the boundary conditions and constraints. They seem to be...
Is there any way to create an incident pressure wave for acoustic analysis in ANSYS? I did notice that in electromagnatic modelling there is an option of creating an incident plane wave.
The pressure is applied at the nodes on a line separating a cylinder2D/circle into two areas. So I guess it is not possible since the remesh will affect the original number of nodes.
I am trying to refine the mesh on the current model. I have some constraints/loads (i.e. FSI, pressure) on the structure and surrounding fluid. But whenever I try to refine the mesh, ANSYS asks me to remove the loads/constraints. I was wondering if there is any way to refine the mesh without...
Well we can also list the solution in Time-History Processor to obtain the amplitude and phase via PRCPLX command.
Just for the sake of knowledge, is it possible to view the solutions for all the nodes rather than just the particular node in Time-History Processor? How can we expand the...
Finally, I figured out how to get contour plots in amplitudes for a given phase angle.
In the POST1, there is a command (HRCPLX) which lets you see the pressure distribution in amplitude for a specified phase angle (phase angle=>360, see the help under this command in ANSYS guide).
Drej as you...
hi Drej,
I did try HROUT,OFF but the pressure contour plot still displays real and imaginary solution. Even when you solve the current LS, the status window ensures that the solution will be amplitude and phase, if you have chosen that.
For the harmonic model that I have, I need the solutions as amplitude and phase. Even though I select amplitued and phase in "Analysis Options". The contour plot displays the real and imaginary solutions. my models consists of a 2D cylinder surrounded with air. The pressure loads are applied at...
Unfortunately, the changing the tolerance is not helping either. I increased the tolerence up to 1e-10 but I get the same error message as I stated above. If I lower the tolerence , I would get an error message asking me to change the tolerance settings.
Hi TGS4,
I think you're right. The scaling seems to be the problem. Because I tried creating the hollow sphere with different and bigger sets of radii (ie. (12,7) and (10,7)).
Well, I am wondering if there is any efficient way to get away without changing the scales and units.
BTW, Thanks for...
I am trying to divide the sphere in two parts but having a problem doing it.
Here's what I did.
- I created a hollow sphere with R1 = 10e-6 and R2=77.5e-6
_ To divide the sphere into two volumes, I created the rectangle area with x1,x2=(77.5e-6,-77.5e-6) and y1,y2= (77.5e-6,-77.5e-6) and...
I'm performing the ultrasound scattering simulations. As a boundary condition I need to create a pulse/plane wave. Since the elements types that I'm using do not have electro magnetic properties, I cant use "Preprocessor>Loads>Define Loads>Apply>Electric>Excitation>Planewav0>Define Wave".
But I...
Thanks Cloche..
This is exactly what I had in my mind. I have to define HF series element types which has electro-magnetic properties. I tried Preprocessor>Physics>Coupled Solvers>Elec/Struc, but dont know how to play around with it. Anyhow, there must be another approach to this problem...
Also, I used the following elements types:
SOLID45 (solid sphere)
FLUID30 (water-with both structure present and absent option )
FLUID130 (Absorption Boundary)
I am trying to model the scattering of biological cell. So far what I have is a solid sphere (cell with elastic properties) inside a hollow sphere (FLUID-Water) with fluid-solid interface and aborption boundary. Technically, this is a fluid-structure coupled acoustic analysis.
Only thing I am...