On modeling runner included into a hydroacoustic system

29th IAHR Symposium on Hydraulic Machinery and Systems

Borodulin, V.Yu.^1 ; Dekterev, A.A.^1 ; Kuibin, P.A.^1 ; Minakov, A.V.^1 ; Semenov, G.A.^2 ; Zakharov, A.V.^2

Kutateladze Institute of Thermophysics SB RAS, 1 Lavrentyev ave., Novosibirsk

630090, Russia^1

PJSC 'Power Machines' LMZ, 18, Sverdlovskaya nab., St.-Petersburg

195009, Russia^2

关键词: Acoustic signals;    Disturbance frequency;    Electrical circuit;    Equivalent resistance;    Hydro-acoustic system;    One-dimensional approach;    Operation point;    Part load conditions;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/240/2/022047/pdf
DOI  :  10.1088/1755-1315/240/2/022047

来源: IOP

【 摘 要 】

Francis turbines operating at part load condition experience the development of non-stationary phenomena and there is a risk of resonance in the case when the disturbance frequencies are close to the eigen hydroacoustic frequencies of the waterway. Usual way for analysis of the hydroacoustic phenomena is an one-dimensional approach when the flow duct is divided into elementary parts, which, in turn, have being modeled by elements of an electrical circuit with equivalent resistances, capacitances, and inductances. Such approach was presented in details by Nicolet (2007) in his thesis. The most serious milestone in use of the electric circuit analogy lies in the problem, how the resistance, capacitance, and inductance of the turbine runner can be evaluated. The simplest approach is reduced to determination of resistance only through universal characteristic of the turbine. In the same time, one should understand that in the wave phenomenon both, the amplitude and phase will be changed during pass over the runner. In this paper, we propose an approach for modeling hydroacoustic phenomena, where the data on the passage of an acoustic signal through the system "spiral chamber - stator columns - guide vanes - runner" are taken from the CFD calculations. That is, during calculation of the flow in this system at some operation point we fix relations between the amplitude and phase of the pressure and discharge pulsations at the input into the system and its output and then use them as characteristics of element of hydroacoustic electric-like chain.