基于遗传算法的潮流能水轮机翼型优化设计

为了获得满足潮流能水轮机设计要求的专用翼型,基于遗传算法建立了水轮机翼型优化设计模型,该模型综合考虑了升力系数、阻力系数、升阻比和压力系数等因素,采用XFOIL评估翼型的水动力性能,对几种典型设计要求情况下的水轮机翼型进行了优化设计.数值结果表明,该模型能够根据不同的设计要求获得相对应的水轮机翼型,不仅可以改善翼型的水动力系数,还能够避免翼型空化现象的产生.在最小化压力系数情况下,最大厚度位置更靠近翼型后缘,而最大化升力系数情况下则更靠近翼型前缘.为了达到指定的设计目标,需要考虑多个攻角下的升力系数或压力系数.

Tidal Turbine Hydrofoil Design Method Based on Genetic Algorithm

To give the specific hydrofoil for tidal turbine, the design optimization method for hydrofoil was investigated. The proposed approach was based on genetic algorithm. The function of lift coefficient, lift-drag ratio, drag coefficient and pressure coefficient were chosen as the objective functions. XFOIL software was employed to evaluate the hydrodynamic efficiency and pressure on the surface. Several typical design objective functions were established under different design requirements, and the corresponding hydrofoil curves were given in the proposed method. Numerical result shows that this approach can deal with the hydrofoil design optimization problem for tidal turbine according to the specific design requirement. The given hydrofoil can not only improve hydrodynamic coefficient but also avoid its cavitation problem. The location of maximum thickness is closer to trailing edge for minimized pressure coefficient, while it approaches the leading edge under maximized lift coefficient condition. The hydrodynamic efficiency and pressure distribution for various attack angles should be considered to achieve the designated objective function.