Messages

46

Fluent / How can I copy my case settings from one case to new case?

« on: April 25, 2012, 10:25:13 AM »

I want to copy one case to a new case in Fluent. How can I do that?

47

Meshing / Re: conv-div nozzle geometry

« on: April 25, 2012, 08:42:57 AM »

You can use an input file for ICEM script.
Or you can draw the geometry using Autocad and then import it into ICEM.

48

Fluent / Cavitation model with dynamic mesh doesn't converge!

« on: April 10, 2012, 10:27:45 AM »

Hello,

Cavitation model with dynamic mesh doesn't converge!!! The case carries pressure bcs.

Please help.

49

Fluent / How can I enable smoothing for hex mesh?

« on: April 10, 2012, 10:22:26 AM »

Hello,

How can I enable mesh smoothing in Fluent for hexahedral cells?

Thanks.

50

Meshing / Re: conv-div nozzle geometry

« on: April 10, 2012, 10:11:32 AM »

The following guidelines may be of some use to your case:

http://www.scribd.com/doc/50415555/2/Step-2-Creating-the-Geometry-in-ANSYS-DesignModeler

51

Matlab / Re: How do I solve two Ordinary Differential equations using Matlab

« on: April 06, 2012, 10:51:07 AM »

In the Matlab editor write the following code:

Code: [Select]

function yp = programs(t,y)

xx=y(1);
tt=y(2);


yp1=5.18*(1-xx)/tt;
yp2=3.165*(1-xx)+0.4*(300-tt);


yp=[yp1;yp2];

Save this file as programs.m
Then add it to the path by clicking the run button.

Now to solve the equations type the following code in the workspace window:

[t,y]=ode45(@programs,[0 5], [0,20])


[0 5] is the initial and final value of time (assuming that you are differentiating with respect to time). [0,20] is the initial values of the variables:  x and T.

To plot the results, you can use the plot function. Type the following code in the workspace window:

plotyy(t,y(:,1),t,y(:,2));

52

CFX / How do I specify Boundary Conditions correctly in CFX?

« on: February 13, 2012, 09:16:26 PM »

I am new to CFX, how do I specify Boundary Conditions correctly?

Thank you.

53

CFX / How do I simulate fires in CFX?

« on: February 13, 2012, 09:11:06 PM »

Hi,

I am new to CFX, how do I simulate fire in CFX?

Please help.

Thank you.

54

Fluent / The calculated temperatures is lower than specified temperature

« on: February 13, 2012, 09:03:12 PM »

Hi,

I am running a simulation with energy equation activated. The temperature at the outlet is lower than the specified temperature at the inlet. I have tetrahedral mesh.

Please help.

Thanks.

55

Fluent / Cavitation model with dynamic mesh doesn't converge!!!

« on: February 13, 2012, 08:55:29 PM »

Hi,

Cavitation model with dynamic mesh doesn't converge in Fluent 6.3. Please help.

56

Fluent / How to identify cells at the interface for heat and mass transfer in VOF Fluent?

« on: February 11, 2012, 01:54:52 PM »

Hi,

How do I identify the cells at the interface for heat and mass transfer at the interface in VOF model in fluent? Can any one help here?

Thanks.

57

Fluent / Error: Divergence detected in AMG solver: x-momentum

« on: February 11, 2012, 01:11:52 PM »

Why am I getting divergence on the first iteration for an axisymmetric problem?

I am running a 2d axisymmetric simulation but it diverges on the first iteration with the following message:

Divergence detected in AMG solver: x-momentum -> Increasing relaxation sweeps!

Error: Divergence detected in AMG solver: x-momentum
Error Object: #f

58

Fluent / VOF simulation diverges, error message Global courant number is greater than 250

« on: February 08, 2012, 10:10:30 AM »

Hi,

The VOF simulation diverges with the error message: Global courant number is greater than 250. The velocity field is probably diverging?

Can someone help me?

59

Fluent / How to create a UDF for mass weighted average function on a surface?

« on: February 06, 2012, 07:05:17 PM »

I want to make a UDF which I can use for calculating mass-weighed average of the properties on a specified surface. Can any one give me something to start with?

Thanks.

60

Fluent / How can I remove a particle from a domain using UDF?

« on: February 06, 2012, 06:46:12 PM »

Hello,

I am doing multiphase simulation with particles tracked using lagrangian approach. I want to set a condition that when the particles hit a certain location in the geometry, the particles should get removed from the simulation. Its heat and mass balance along with it.

Can any one suggest me how to do this?

Thank you.