cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Showing results for 
Search instead for 
Did you mean: 

Community Tip - Did you know you can set a signature that will be added to all your posts? Set it here! X

Diffusive emissions in a mixed chamber

gourish
3-Visitor

Diffusive emissions in a mixed chamber

I am trying to solve PDE which has one of the boundary conditions an ODE. I am having problems - please help. I am attaching a mathcad sheet as well as a word document that describes the original problem

Gourish

7 REPLIES 7
AndyWesterman
4-Participant
(To:gourish)

Hi Gourash,

I think that there may be an error in one or more of your equations.

1

Capture.PNG

Cs(1,0)=CS0

2

Capture.PNG

Cs(1,0)=0

Obviously give contradicting boundary conditions.

Regards

Andy

Thank you for pointing out the inconsistencey in ICs. Attached is a new xmcd. I have combined the variables and all my equations are with respect to Cs. I am not sure if the syntax of Ct (1.t) is allowed. I am still getting error in Pdesolve statement.

Help Please!. Thanks.

You may check your equations again.If you disable the third equation, Mathcad finds a solution!? I would have expected the system to be underdetermined then.

AndyWesterman
4-Participant
(To:gourish)

Hi Gourash,

Have stayed with your original idea for equations with Cs & y.

I have modified the initial conditon for y(?,t) & it produces an answer.

There is a noticeable error (as shown on the graphs) but not sure whether this is acceptable to yo for your application.

It is very sensitive to variation in initial conditions, but hope it is helpful.

Regards

Andy

Hello Andy,

Thank you very much for your response. I am not able to open mathcad file because I have MathCad 13.0. Would it be possible to save it 13.0 format and reattach. Thanks again

Regards,

Gourish

File saved in mathacd12 and 13.

AndyWesterman
4-Participant
(To:gourish)

Hi Gourish,

Saved as 13.0 - hope it works for you.

Regards

Andy

Top Tags