HYDRAULIC RESISTANCE OF 2-PHASE FLOW IN PIPES WITH POROUS COATING

Results are given of the experimental investigation of hydraulic resistance of two-phase flows in pipes with porous coatings. The friction coefficient in the domain of a square law of resistance for a pipe 8 mm in diameter with a porous coating of thickness k(h) = 200 mcm is shown to exceed the values of xi for a smooth-walled pipe by 4-5 times, those for industrially rough pipes by 3 times, and those for pipes with sand roughness equivalent to the coating thickness by about 1.4 times. It is found that the roughness of the channel walls due to corpuscular porous coatings is not the only factor responsible for an increase of hydraulic resistance governed mainly by hydrodynamic processes in the pore space of coatings.