桨后扭曲舵的理论设计及水动力性能计算

采用面元法计算了螺旋桨与舵之间相互干扰的水动力性能并在此基础上设计出扭曲舵,采用迭代处理计算了螺旋桨与桨后扭曲舵相互干扰的定常水动力性能.在计算面元的影响系数时,应用了Morino导出的解析计算公式,以加快数值的计算速度.分析比较了不同进数系数时,普通舵与扭曲舵的助推效率.对于两者在不同进数系数下的操舵力矩进行了比较,与普通舵相比扭曲舵并未使船舶的操舵力矩恶化.计算结果表明,该设计的扭曲舵与普通舵相比可以产生附加推力,能够吸收螺旋桨的尾流动能起到助推节能的作用,最大助推效率可以达到3%.

Design and performance of a skew rudder behind a propeller

A skew rudder was designed based on calculations of propeller-rudder interaction.First,the panel method was used to define the surfaces of a propeller and a skew rudder.The computation of hydrodynamic interaction between them was treated by iteration.In the process of calculating the influence coefficients of the panels,an analytical formula based on Morino's idea was employed to speed up the numerical calculations.The additional thrust and torque coefficients generated by a conventional rudder and a skew rudder were compared.The findings indicate that a skew rudder increases thrust significantly,but the torque does not change a lot.The proposed skew rudder can absorb rotational energy and supply additional thrust up to about 3 percent of propeller thrust.