Finding Flow of Non-Newtonian Fluids in Circular Pipe with Wall-Adjacent Gas Layer

摘要

The paper describes the existing flow models for high-viscosity fluids flowing through a circular pipe with a wall-adjacent low-viscosity layer; the models considered are used to design devices to induce such flow of viscous and highly viscous fluids. The paper parameterizes the flow of fuel oil in a wall-adjacent gas layer, using a known mathematical model of two-layer annular flow of non-Newtonian fluids within a low-viscosity boundary layer. The research team has designed an experimental setup that contains a device for generating two-layer annular flow. The process has been studied experimentally. Primary-fluid and gas flow rates that are necessary for stable annular flow have been found empirically. The paper derives a regression equation to find the fuel-oil and air flow necessary to generate a wall-adjacent gas layer. Mathematical statistics proves the regression equation adequate. The resultant regression equation is recommendable for use to find the wall-adjacent gas flow to generate stable annular fuel-oil flow in a rough-surfaced steel pipe when designing industrial pipelines and networks.