Abstract: Operation of Francis turbines in part load and sometimes in full load operating points is associated with increased pressure pulsations. One of the practical ways to reduce these pulsations is to add atmospheric air into the flow. It was shown previously that air injection/admission through the center of the runner cone can significantly reduce the amplitude of pressure pulsations both in part load and in full load operating points. Up to now the effect of flow aeration has been investigated mainly experimentally. In the present paper we performed CFD simulations of this phenomenon. Computations have been carried out in frames of homogeneous three-phase “liquid – vapor – non-condensable gas” mixture model. Air phase has been assumed incompressible. Both part load and full load operating points have been considered with different air flow rates. Computations have shown that even at small flow rate the air changes the structure of the swirling flow downstream the runner and considerably reduces pressure pulsations, caused by vortex rope rotation. The obtained results are in agreement with corresponding experimental data for model turbine.

Cite: Chirkov D. , Scherbakov P. , Skorospelov V. , Cherny S. , Zakharov A.
Numerical simulation of air injection in Francis turbine
IOP Conference Series: Earth and Environmental Science. 2019. V.240. N2. 022043 :1-1. DOI: 10.1088/1755-1315/240/2/022043 Scopus OpenAlex

Identifiers:

Scopus:	2-s2.0-85063889149
OpenAlex:	W2925686925

Citing:

DB	Citing
Scopus	12
OpenAlex	10

Altmetrics: