USE OF COUPLED BOUNDARY AND FINITE ELEMENTS METHOD FOR ANALISYS OF RESONANCE FREQUENCIES OF RUNNER OF HYDROTURBINE

The coupled finite and boundary elements method used to study the resonant frequencies of the two variants construction of the runner hydraulic turbine. For this purpose was construct the mathematical model of the runner in cyclosymmetry statement. Calculation of stress-strain state of the runner showed that the thickening of the trailing edge reduces the equivalent stresses. Studies have shown that thickening of the trailing edge of the runner blade has almost no effect on the values of the natural frequencies. The analysis of the resonant frequency of the runner and the frequency spectrum of the excitation forces achieved. The results showed that values first and second natural frequency isolated blade in water matched with the natural frequency full runner. New physical effects of the interaction of the blade with the "light" and "heavy" acoustic environments found.