In order to improve the cycle efficiency of the ocean thermal energy conversion (OTEC), the performance of a radial inflow turbine is studied. Based on the 1-D thermodynamic design of the turbine with the main parameters determined by experience and modified by a genetic algorithm, an aerodynamic model of the turbine is built through the 3-D design of the volute, the nozzle and the impeller. The performance of the turbine under the design condition is studied by the computational fluid dynamics (CFD) and the numerical results show that the turbine efficiency is 86.5%. Finally, it is shown that the turbine has a good performance when the nozzle-impeller relative radial clearance is 0.04 and the nozzle stagger installation is about 37°. Therefore, the nozzle-impeller radial clearance and the nozzle installation angle can be fine-adjusted to obtain a higher turbine efficiency under the design condition; and under the non-design conditions. An adjustable nozzle mechanism can be used under the off-design conditions to put the turbine in a good working state under various working conditions.

ocean thermal energy  /  power generation system  /  turbine aerodynamic efficiency