英语翻译Numerical calculations are carried out for JD7704 simplified ducted propeller series and 19A ducted propeller series.Based on the investigations in paragraph 3,circumferential nonaveraged induced velocities on the duct and BTKI=0.43 are a

英语翻译Numerical calculations are carried out for JD7704 simplified ducted propeller series and 19A ducted propeller series.Based on the investigations in paragraph 3,circumferential nonaveraged induced velocities on the duct and BTKI=0.43 are a
英语翻译
Numerical calculations are carried out for JD7704 simplified ducted propeller series and 19A ducted propeller series.Based on the investigations in paragraph 3,circumferential nonaveraged induced velocities on the duct and BTKI=0.43 are adopted for JD7704+KA,19a+KA propeller series.Corresponding results are shown in Figs.10- 12 and Figs.13- 16 for JD7704+KA and 19a+KA propeller series respectively.The“0.43 Cf- PS nav”in figures denotes that BTKI=0.43,the friction drag coefficient is computed by Prandtl- Schlichtin formula,and circumferential non- averaged induced velocities on the duct is applied.In addition,a ducted propeller with PF- W- C (P/D =1.236) propeller and PF- W- D duct provided by MARINTEK is also calculated.Results are described in Fig.17.Results obtained by the coupling method of lifting surface theory and panel method,“NAV_Wbs BEM/LSM”,are also given in the same
figure for comparison.“0.43 NAV BEM”means BTKI=0.43,non- averaged induced velocity on duct surface due to propeller and panel method are used in the calculation.
A numerical study is conducted on open water characteristics and the hydrodynamic
spindle torque of JD7704 duct together with JDC Controllable Pitch Propeller series
[13].Figs.18- 19 show the numerical and experimental results of JD7704 duct with JDC series at design condition,i.e.the blades have no rotation angle around the spindle axes.In this case BT-KI=0.48 is employed in the calculations as mentioned above.Fig.20 gives the hydrodynamic performances,including open water characteristics and spindle toque,of JD7704 +JDC7703 ducted CPP at design and off- design conditions.In figure,“BEM - 10,0,10 deg.”means that results are obtained by panel method at blade angle- 10,0,and 10 degree.“LSM/BEM- 10,0,10 deg.”means that corresponding results are obtained by coupled method of lifting surface theory and panel method

英语翻译Numerical calculations are carried out for JD7704 simplified ducted propeller series and 19A ducted propeller series.Based on the investigations in paragraph 3,circumferential nonaveraged induced velocities on the duct and BTKI=0.43 are a
将JD7704导管螺旋桨系列和19A导管螺旋桨系列的计算结果进行了简化.根据第三条款的规定,圆周诱导速度在管道BTKI = 0.43时采用JD7704 + KA,19 a + KA螺旋桨系列.相应的结果显示在图上.图10—12和图13—16分别为JD7704 + KA和19 a + KA螺旋桨系列.“0.43 Cf – PS”图表示,BTKI = 0.43,普朗特-许立丁摩擦阻力系数的计算公式,和在管道应用中周向非平均诱导速度.此外,一个导管螺旋桨与PF – W – C(P / D = 1.236)螺旋桨和PF – W – D管提供了MARINTEK计算,结果在图17中被描述.用耦合方法的升力面理论和面板的方法得到的结果,“NAV_Wbs BEM/LSM”,在给出的一个图中进行了比较.“0.43 NAV BEM”的意思是BTKI=0.43,用于计算非平均诱导速度在管表面的一种方法.
一个数值研究在开放水特性和水动力轴转矩的JD7704管连同JDC系列可变螺距螺旋桨上进行.图18—19显示JD7704 JDC系列的管道在设计条件下数值和实验结果.在主轴处,叶片没有旋转角.如上所述,在这种情况下BTKI = 0.48是受限于计算.图20给出了水动力性能,包括敞水特性,JD7704 + JDC7703导管CPP在设计和关闭——设计条件.在图形中,“边界元—10,0、0度”的意思是用面板法的方法得到了叶片在角—10,0、10度时的结果.“LSM/BEM- 10,0,10 deg”的意思是得到了用耦合方法的升力面理论和面板方法的相应结果.