Accession Number:

AD0723590

Title:

Hydraulic Resistance in a Two Phase Flow,

Descriptive Note:

Corporate Author:

NAVAL SCIENTIFIC AND TECHNICAL INFORMATION CENTRE ORPINGTON (ENGLAND)

Personal Author(s):

Report Date:

1971-03-01

Pagination or Media Count:

13.0

Abstract:

When considering the problem of intensifying mass-transmission processes, the hydrodynamic problem of the joint movement of a gas stream and a liquid film wetting the inner wall of a cylindrical channel assumes special significance. In particular, there is the important question of the hydraulic resistance of such a two phase system during change of average speeds and physical characteristics of the interacting phases. Experimental data on hydraulic resistance of condenser tubes in conditions of the phases flowing in the same direction and oposite directions with constant wetting thickness, shows that the resistance of a two phase system has a number of pecularities which testify to the qualitative difference between this type of flow and the normal single phase flow. Thus, at a certain critical gas flow speed corresponding to the change from opposite flow to unidirectional flow, a sharp rise in resistance is observed. With further increase in speed of the gas phase the resistance falls, reaches a certain minimum value and then increases again. In this way every fixed wetting has a clearly defined minimum of fall of pressure. The existence of a flow region where with the increase of gas speed resistance falls seems at first sight to contradict natural laws. The apparent contradiction is explained by solving the equation of motion in the liquid phase. Author

Subject Categories:

  • Pumps, Filters, Pipes, Tubing, Fittings and Valves
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE