回转体-螺旋桨组合体之推力减额的一个数值预测方法

作者把计算回转体绕流的Landweber方法推广到带有运转螺旋桨时回转体绕流问题的计算,导出了附加螺旋桨影响后的物面速度分布的第一类Fredh-olm积分方程。对该方程的迭代求解则用新的加速迭代公式替代常用的Land-weber迭代公式。通过对带与不带运转螺旋桨时回转体上压力差的积分可以得到推力减额。两条模型(分别在风洞、水池的试验)的数值例子表明:本方法的迭代速度要比Landweber迭代公式快,而计算得的推力减额和表面压差分布与试验结果的一致性很好,优于Huaug用Hess-Smith方法算得的结果。

A NUMERICAL METHOD TO PREDICT THE THRUST DEDUCTION OF A PROPELLER BEHIND A BODY OF REVOLUTION

Landweber's method of calculating potential flow about body of revolution has been extended to calculate potential flow about the same body with propeller in operation. A First Fredholm integral equation satisfying the velocity distribution affected by propeller-hull interaction on hull is introduced. For solving this equation, Landweber's iteration method is replaced by a new accelerated iteration formula. Thrust deduction is then derived by integration of pressure-defect on the hull with and without a propeller in operation.The merit of this technique is demonstrated by its application to two different models tested in towing tank and wind tunnel. The calculating speed of this iteration method is faster than that of Landweber's iterated method and the numerical results relating to thrust deduction and pres-suredefect distribution on hull agree well with those obtained from the experiments, and are better than those obtained by Huang using Hess-Sm-ith method.