Siberian Federal University

Issue

Journal of Siberian Federal University. Engineering & Technologies. 2022 15 (6)

Authors

Gavrilov, Andrey A.; Dekterev, Aleksandr A.

Contact information

Dekterev, Aleksandr A.: Siberian Federal University Krasnoyarsk, Russian Federation; Institute of Thermophysics S. S. Kutateladze SB RAS Krasnoyarsk Branch Krasnoyarsk, Russian Federation;

Keywords

flow in a hydraulic turbine; swirling flow; vortex; URANS, LES and PANS turbulence models; velocity fluctuations; numerical simulation

Abstract

Swirling flows are widespread in various fields of technology. At a high degree of swirling, the flow is complicated by the collapse of the vortex and the formation of large-scale unsteady structures. In hydropower engineering, the swirling flow instability is manifested by a precessing’s vortex bundle in the suction pipe. These non-stationary structures have a significant turbulent kinetic energy and are characterized by a sufficiently long lifetime, which causes serious difficulties in the numerical simulation of flows in the duct of hydraulic turbines. The aim of this work is to construct a hybrid PANS turbulence model based on a second-order closure model. Using this model with different values of the resolution parameter, numerical calculations of the unsteady flow in the draft pipe in the partial load mode were performed. The proposed version of the PANS turbulence model makes it possible to reproduce well the characteristics of highly anisotropic flows, while being less demanding on the grid resolution than the large eddy simulation method, and in the considered implementation does not contain an explicit dependence on the spatial grid spacing

Pages

726–738

DOI

10.17516/1999-494X-0430

Paper at repository of SibFU

https://elib.sfu-kras.ru/handle/2311/149202

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).