How can I fix the sign issue in my NDSolve command in Mathematica?

[burcuugur]

Hi,

I'm trying to model a process by making mass and energy balances using the NDSolve. It reaches the maximum number of steps

It is working when I put "-" sign in front of this [Rho]p*(1 - ec)*\[CapitalDelta]H*D[q[z, t], t] (in 3rd equation) in the NDSolve command. But it should be "+" sign.

I attached the mathematica file.

I would really appreciate some help. This is really important for me.

 

[Bill Simpson]

I attached the mathematica file.

I don't see the attached notebook. Perhaps something didn't get clicked on. Perhaps there is some restriction involved.

If you could simplify your problem down enough that you could just scrape your NDSolve[] expression, paste it into your post and then edit it to make certain that it was all readable then that might be enough.

If you scrape and paste then carefully check it after you complete the post and edit as necessary to make certain it is all there and readable.

 

[burcuugur]

Sorry for that. I attached it now.

 

[FunkyDwarf]

MaxSteps->more?

 

[alphy]

Hello,

Thank you for reaching out for help with your NDSolve in Mathematica. It seems like you are experiencing some issues with the sign in your third equation. Have you tried double-checking your calculations and equations to make sure that the sign is indeed supposed to be a "+" sign? It's possible that there may be a mistake in your calculations that is causing the issue.

Additionally, I would recommend reaching out to the Mathematica community or forums for more specific and detailed help with your code. There are many experienced users who may be able to provide insight and assistance in troubleshooting your NDSolve. Good luck with your modeling process!