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 Prashant May 7, 2008 05:05

solve the mixing of gases

Hi All,

I am new to Fluent. I have a problem in solving the below problem. I have a two chambers A and B. B area is 50 times larger than the A.

|---------|

|----| |

| A | B |

|----| |

| |

|---------|

The condition of the gas is Gas A----2.05 bar, 400 K Gas B----2.00 bar, 300 K

I initialise the 2.00 bar, and 300 K and patching zone A with 2.05 bar,400 K. but the problem is It TAKES TEMPERATURE VALUES CORRECTLY BUT PRESSURE, IT SHOWS DIFFERENT VALUES. First thought it might be problem with operating pressure. and tryed changing it to zero gauge pressure. then also the same problem ( pressure difference is different)

Please, help me to solve this problem.

Regards, Prashant

 Prashant May 7, 2008 05:07

Re: solve the mixing of gases

In the above the figure is not shown correctly. The A and B chambers are side by side

A | B

 CFD May 8, 2008 02:20

Re: solve the mixing of gases

First Initialize Default values and patch each zone carefully,and check the pressure in each zone at initial conditions

and how do you sepparate both zones (boundary condition)?

 AAA May 8, 2008 15:42

Re: solve the mixing of gases

Hi

maybe the problem is not setup correctly. What BCs are you using? Are you using unsteady simulation? What results are you trying to obtain?

Something that might be of help, go to Report-->Reference values and check the pressure there.

Regards

AAA

 Prashant May 21, 2008 00:51

Re: solve the mixing of gases

sorry,

I have seperated the zones using interior BC in GAMBIT itself. So, when imported it will create two zones.

And the

A and B chambers are closed. So all the outside walls are given the temperature BC. But, whn I initialised the values

it assumes only 1.01325 bar as the pressure, u give whatever the values. Refernce value is set zero.

And When I tryed to patch the values. the max value is taken as : 1.01325 + patch,

min : 1.01325 - patch, for whole geometry. But, the temperature values is whatever the value has been patched.

I want to simulate the A is at 2.05 bar n 400 K, B is at 2.00 bar n 300 K.

by looking at the problem it seems simple. I am new to FLUENT. But, don't know how to solve this one. If anybody know, please let me know.