The concept of turbulent «vortex backfill» - models and methods. Power engineering: research, equipment, technology

Abstract

Models and methods for studying turbulence based on the concept of turbulent "vortex backfill" are presented. The essence of this concept is that the turbulent flow is considered as laminar, flowing through a "vortex backfill ", which creates internal resistance. This resistance can be considered either as distributed, or as locally concentrated. Based on the first representation, a modified Navier-Stokes equation, its approximate analytical and numerical solutions are obtained. Based on the second concept and the local fluctuation method developed for these purposes, a computer model of the turbulent flow in the pipes is obtained. Using simulation, it is shown that, when a certain system of local viscosity fluctuations is specified, the calculated flow profile corresponds to the profile of the turbulent flow velocity. The magnitude and profile of the turbulent viscosity of the flow are completely determined by the structure and properties of the "vortex backfill ". The results of the work confirm the possibility and efficiency of considering turbulence based on this concept.

Keywords

• turbulence
• «vortex backfill»
• simulation
• local fluctuations