I am a PhD student at Istanbul Technical University. I wrote a solver for 3D Euler eqns in polar coordinates and now want to add viscous effects. I need some information about books and papers for that reason.

Thanks in advance

It's not clear what you are trying to do with 3D Euler equations and viscous effect. Euler equations are derived from Navier-Stokes equations without the viscous terms. You can find the Navier-Stokes equations in the standard fluid mechanics text books.( in Cartesian or cylindrical coordinates ) If you are interested in turbulent flows, most people started with Reynolds averaged equations which are also covered in the standard text book. If you are talking about adding a viscous term for numerical stability, then it's a different story.