@tomleslie 

Thank you for your reply. I am sorry about how upload the code. I am still new to Maple and to this website. I have four boundary conditions but they are not in term of u and w. they are in terms of ∂u/∂r, ∂w/∂z,...etc. Does that work for my problem?

I attached the code, so if you have time to help, I will be appreciated.

Thank you.

PDE_equation2.mw

@tomleslie Thank you, I figured it out.