有机工质向心透平数值模拟及变工况内流特性研究

Based on the research status at home and abroad, 3D numerical simulations were carried out for an organic Rankine cycle turbine under design and off-design conditions respectively. Taking turbine power, efficiency, reaction, stator blade loss coefficient, and rotor blade loss coefficient as evaluation indexes, the performance of the turbine under off-design conditions was analyzed. At the same time, the flow condition of the turbine under off-design conditions was described. Results show that the turbine output power is 122. 3 kW and the turbine isentropic efficiency is 83. 54% under design condition. While under off-design conditions, the turbine power and efficiency increase greatly when the speed ratio is 0. 8-1. 0. The reaction coefficient and stator blade loss coefficient of the turbine are linear with the speed, while the rotor blade loss coefficient has a minimum value when the speed ratio is 0. 8-1. 2. When the rotating speed is lower than the design value, vortices exist on the suction surface of the leading edge of the rotor blade; when the rotating speed is greater than the design speed, vortices exist on the leading edge of the pressure surface of the rotor blade. The main reason for this phenomenon is that there is a difference between the rotating speed of the rotor blade and the circumferential component of the stator blade outlet velocity.