ABSTRACT
In the diversion power generation system of the tailrace tunnel shared by two units, a hydraulic disturbance is an inevitable phenomenon in daily operation, and it is of far-reaching significance to study the influence of hydraulic disturbance on the transition process. In this paper, taking the water diversion power generation system with the layout of “single pipe and single unit” and “two units, one tailrace tunnel” as an example, the mathematical model of the water diversion power generation system is constructed by the characteristic line method. The changes in unit output, the relative opening of guide vanes, relative rotational speed, volute end pressure, draft tube inlet pressure, and surge water level in the draft tube surge chamber during the transition of hydraulic disturbance were calculated. The calculation results show that during the hydraulic disturbance transition process of the dual-unit shared tailrace tunnel diversion power generation system in this paper, the maximum surge in the tailrace surge chamber is 2257.9 m, and the extreme value occurrence time is 39.8 s, and the maximum speed increase rate is 44%. The maximum water pressure of the volute is 308.4 m, all of which meet the design requirements.
