桨叶变形对螺旋桨敞水性能影响及对策研究

Influence of blade′s deformation on open-water performance of marine propellers and its countermeasure

为了定量研究桨叶变形对螺旋桨水动力性能的影响,运用已建立的船舶螺旋桨双向流固耦合稳态求解算法,计算了柔性易变形螺旋桨不同进速下的变形,对比了变形前后螺旋桨的敞水性能曲线.明确了桨叶变形对敞水性能的影响机理,提出桨叶预变形技术以解决柔性易变形桨叶变形引起的螺旋桨性能改变.研究结果表明:初始几何无侧斜无纵倾的螺旋桨变形后的推力和扭矩变大,有侧斜或有纵倾的推力和扭矩变小;同时随着侧斜或纵倾的逐步增大,桨叶变形越大,螺旋桨的敞水性能改变愈明显,则采用预变形改进螺旋桨水动力性能的效果也愈明显;初始几何无侧斜无纵倾的螺旋桨进行预变形设计达不到预期效果.

To quantificationally investigate the influence of the blade deformation on flexible marine propellers′ open-water performance, a two-way fluid-structure interaction method was proposed to calculate the blade deformation at different advance velocities. The open-water curves were compared corresponding to the undeformed and deformed propeller shapes. The influence mechanism of the deformation on open-water performance was found and the countermeasure to resolve the blade deformation, through pre-deformed designs, was given. The results show that after the deformation,the toque and thrust coefficients increase in the case of the propeller without initial rake and shew, but the toque and thrust coefficients decrease in the case of the propeller with rake and skew angle. As the rake or skew angle increases, the blade deformation increases. Greater changes the open-water performance undergo,more evident improvement can be obtained by the pre-deformed design. The propeller without skew and rake angles cannot reach the expected goal to improve the performance through pre-deformed design.