# Laminar Unidirectional Flow

```@inproceedings{Spurk1997LaminarUF,
title={Laminar Unidirectional Flow},
author={Joseph H. Spurk},
year={1997}
}```
Incompressible Newtonian fluid (ϱ η) flows steadily within the annular gap of two infinitely long cylinders (Ro, RI). The outer cylinder rotates with Ω0 the inner one with Ω I . For the case that the axial component of the velocity is equal to zero, calculate a) the velocity and pressure field, b) the moments acting on both cylinders, c) the dissipated power within the gap. d) For what ratio Ω0/Ω I is the flow a potential flow?