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?