SIMULATION OF BOUNDARY LAYER UNDER LAMINAR AND TURBULENT MODES OF NEWTONIAN FLUID MOTION IN A FLEXIBLE PIPELINE
Abstract
The article deals with the modeling of boundary layer parameters for Newtonian fluids under laminar and turbulent modes of motion. Based on the system of Prandtl equations and initial boundary conditions under laminar motion, using the Gallorkin method, a tri-diagonal system of equations is formed, which connects the values of functions at the node of nets n+1 across the boundary layer. The numerical method uses the Thomas algorithm to calculate values Ujn+. The velocity value Vjn+1 is determined from the continuity equation by integration across the boundary layer. The Navier-Stokes equation in dimensionless form was used to model the turbulent boundary layer, given the velocity U is an independent variable. The differential equation system was solved using the numerical Dorodnicin method. The results of modeling the velocity distribution in the boundary layer, the thickness of the boundary layer in the section of the flexible pipeline 0.8-1.5 m from the beginning of the fluid entering the pipeline at the expense up to 0.1 kg/s are presented.
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