On Study Of The Calculation Methods For Hydrodynamic Performance Of The Voith-Schneider And Kobold Rotor

In this paper, different computation methods and the hydrodynamic performance of vertical-axis variable-pitch cycloidal (Voith-Schneider) rotor and Kobold horizontal-axis rotor are studied. Much attention is focus on the comparison and studying of the reliability of the different methods when applied to the two type rotors, which is the important base of the selecting of rotors, the designing of hydrodynamics performance, and the general designing of tidal current power plant.For the vertical-axis variable-pitch cycloidal rotor, the article unify hydrodynamic performance symbol at first, classify and trim the calculation methods and formula of predicting fluid dynamical capability of water-power rotor and wind-power wheel that have been formed up to now. Then, four different computation methods are applied to compute the hydrodynamic performance of the rotor, which are single-disk single-tube method (SDST), double-disk single-tube method (DDST), multi-tube method (MTT) that are based on momentum theorem and vortex method (VTTH) that is based on potential eddy theory. Finally, the numerical results are obtained and every method is analyzed particularly and compared with experimental data [2].For the Kobold horizontal-axis rotor, the hydrodynamic performance is explored and studied gradually. At first, a basic resistance-type method is presented. Then, the methods that have been used to the vertical-axis variable-pitch cycloidal rotor are applied and the corresponding calculation formulas are formed. Finally, the numerical results are presented and compared each other but yet they need farther examination and validation.