Through Flow in Short Annulus of Fine Clearance

A. Ellman, K. Koskinen and M. Vilenius
Institute of Hydraulics and Automation
Tampere University of Technology

ASME International Mechanical Engineering Congress and Exposition, Nov. 12-17, 1995, San Francisco, USA.


The problem of the stationary through-flow of Newtonian fluid across a short annulus of fine clearance has been investigated both theoretically and experimentally. A robust model has been developed by combining the pressure loss influence due to inflow and outflow with the conventional laminar and turbulent pipe flow models. The model has been verified with laboratory tests for different values for the clearance and length of the clearance. The experimental investigations reported are limited to eccentric annulus of smooth surfaces and of fine clearance and water as a fluid media. This model has been proven a good agreement with the laboratory tests. In the case of each test done the developed model gave better accuracy compared to the conventional model for laminar flow in annulus.