摘要

In order to drastically increase the power performance and the operating stability of hydraulic machinery, a new bulb turbine with counter-rotating double-rotor was developed. An adjustable-blade system was applied to both rotors of the turbine. Based on the new concept of fair-blade loading, a logical balance of supply and demand for Euler energies between the two rotors was sought. The blade profiles from hub to tip were designed to keep the equilibrium of Euler energy strictly. By the numerical unsteady flow analysis, the degree of Euler energy balance and the control of their interaction were investigated. The research results show that when the front and rear rotors have the same discharge and head, and is under the same size as that of a single rotor turbine, the sum of output powers from the front and rear rotors was doubled. By analyzing the flow interaction between two rotors and between the outlet of rear rotor and inlet of diffuser, the following conclusions are obtained: the output power is doubled without changing the unit size. The Euler energy interaction between the counter-rotating double-rotor is controlled to be small. The amplitude of hydraulic fluctuations is only about 2% of respective head without pressure surge under the on-cam operation. The rotating torques of the two rotors are compensated with good stability.

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