DBPapers
DOI: 10.5593/sgem2017/31/S12.005

APPLICATION OF VORTEX JET BOUNDARY MODEL FOR DETERMINATION OF FLOW PARAMETERS IN HYDROSYSTEM TAILRACE

Y.A. Kuznetsova, A.G. Pozdeev
Monday 11 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-04-1 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 31, 33-42 pp, DOI: 10.5593/sgem2017/31/S12.005

ABSTRACT

Calculation of the local scour behind the hydrosystem tailrace structures is associated with determination of hydraulic flow parameters, characterized by a sudden increase in the depth. The flow parameters are calculated on the basis of T. von Karman’s integral momentum equation for a submerged turbulent jet. The flow in the hydrosystem tailrace, in accordance with the approach of G. N. Abramovich, is considered as a set of a submerged turbulent jet, a vortex area, and a main flow in the tailrace passage. It allows to obtain a system of integral equations that describe the jet stream according to T. von Karman, an integral momentum equation for the flow in the tailrace passage, and a flow conservation equation for the computational domain. To integrate the resulting system of equations, MathCAD is used. A distinctive feature of the calculation is definition of the distribution boundary based on the vortex model. Results of the calculation of the flow in the tailrace are estimated using different models of turbulent friction. To determine the turbulent friction stress, I. G. Lambert’s function is used, which increases the accuracy of estimation of the calculated parameters. Convergence of the obtained results with the known solution of M. A. Mikhalev is established. These results can be used to refine the modeling of local scours in the hydrosystem tailrace.

Keywords: hydrosystem, local scour, tailrace, turbulent jet, vortex boundary, MathCad