Accession Number : AD0663621

Title :   EFFECT ON THE LUBRICATING PROPERTY OF A SURFACE ON THE TRANSFER PROCESS IN SYSTEMS CONSISTING OF A DROP-FORM LIQUID AND A SOLID,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Smolskii,B. M. ; Elperin,I. T.

Report Date : 15 JUN 1967

Pagination or Media Count : 15

Abstract : A determination was made of the hydrodynamic friction resistance in the flow of a fluid in tubes. Determinations were made of the friction coefficients of tubes made of various materials. The walls of the tubes were rubbed previously with distilled water and with various surface active agents. The effect of the surface active agents appears gradually and reaches a maximum after a period of from 1 to 10 minutes, after which it remains constant. The effect of pulsation velocity and lubricating properties on the lowering of the critical Reynolds number is considered. Measurements were made of the temperature of the water, its flow rate through the tube, the duration of the test, and the frequency of the pulsations. The equipment permitted visual observation of the transition point from laminar to turbulent flow, and determination of the critical Reynolds number, which lay within the limits of 2250-2350. A second series of experiments was made to determine the effect of lubricating properties on the lowering of the critical Reynolds number. It was found that, with application of pulsation to flow in a tube which has been treated with surface active agents, the critical Reynolds number has lowered to 1200-1300. Finally, the article considers the effect of lubricating properties on heat transfer.

Descriptors :   (*TWO PHASE FLOW, TRANSPORT PROPERTIES), (*LUBRICATION, TWO PHASE FLOW), LIQUIDS, SOLIDS, DRAG, HYDRODYNAMICS, PIPES, HEAT TRANSFER, MASS TRANSFER, DROPS, USSR

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE