英语翻译As mentioned above,when the velocity on the duct induced by propeller is computed,two different treatments are applied.Fig.4 gives the comparison of results obtained by two treatments,in which“CAV”and“NAV”denote circumferentially

英语翻译As mentioned above,when the velocity on the duct induced by propeller is computed,two different treatments are applied.Fig.4 gives the comparison of results obtained by two treatments,in which“CAV”and“NAV”denote circumferentially
英语翻译
As mentioned above,when the velocity on the duct induced by propeller is computed,two different treatments are applied.Fig.4 gives the comparison of results obtained by two treatments,in which“CAV”and“NAV”denote circumferentially averaged and not averaged treatments respectively.It is seen from Fig.4 that the thrust of duct at lowadvance coefficient can be improved when the induced velocity of propeller to duct is not circumferentially averaged,namely the wake behind the duct exists.This conclusion is coincident with that from Ref.[7].
In Figs.5 and 6,parameter BTKI is a coefficient determining the hydrodynamic pitch angle in the transition region of the wake of propeller.Usually BTKI=0.5 is adopted by panel method for the single propeller.It can be seen from Figs.5 and 6 that BTKI=0.43 gives better results for the case of JD7704 duct+KA propeller series and BTKI=0.48 for the case of JD7704 duct + JDC propeller series.
In the numerical calculations of panel method,the trialing wake sheet of the propellerand duct are truncated at certain distance behind the propeller or duct.Fig.7 shows that reasonable results can be obtained when transition wake range of the propeller is 1080 degrees.It is found from the Fig.8 that the numerical result becomes converged gradually with the increment of region of trailing vortex wake of duct,and there will be no effect on the thrust of duct if the wake length of the duct is over four times of the length of the duct,which will be used in the following calculations.Fig.9 shows that the contraction coefficient of the transition wake of the propeller,RW0,makes no influence on the calculated results,even RW0=0.83,0.98 or 1.0 (“No Contra”in the figure).RW0=0.83 is adopted in the present paper.

英语翻译As mentioned above,when the velocity on the duct induced by propeller is computed,two different treatments are applied.Fig.4 gives the comparison of results obtained by two treatments,in which“CAV”and“NAV”denote circumferentially
如上述提到的,当计算出由螺旋桨在导管上引起的周转率时,可应用两种措施.图4给出了两种措施的结果比较,分别在“恒定角速率”及“NAV " 环绕地表示平均处理与不平均处理时的情况.从图4看出当螺旋桨的诱导速度对导管环绕不平均时,低推进系数上的导管推力可以得到改善,也就是说导管后面的尾迹是存在的.这个结论与文献[7]是一致的.
在图5和图6,BTKI参数决定了螺旋桨尾迹的转变区水动力螺距角的系数.通常BTKI=0.5时单一螺旋桨采用板块法.从图5和图6可看出,当BTKI=0.43时,对JD7704 导管+KA螺旋桨系列与BTKI=0.48时,对JD7704导管+JDC螺旋桨系列可以给出更好的结果.

As mentioned above,when the velocity on the duct induced by propeller is computed,two different treatments are applied.Fig.4 gives the comparison of results obtained by two treatments,in which“CAV”and...

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As mentioned above,when the velocity on the duct induced by propeller is computed,two different treatments are applied.Fig.4 gives the comparison of results obtained by two treatments,in which“CAV”and“NAV”denote circumferentially averaged and not averaged treatments respectively.It is seen from Fig.4 that the thrust of duct at lowadvance coefficient can be improved when the induced velocity of propeller to duct is not circumferentially averaged,namely the wake behind the duct exists. This conclusion is coincident with that from Ref.[7].
In Figs.5 and 6,parameter BTKI is a coefficient determining the hydrodynamic pitch angle in the transition region of the wake of propeller.Usually BTKI=0.5 is adopted by panel method for the single propeller.It can be seen from Figs.5 and 6 that BTKI=0.43 gives better results for the case of JD7704 duct+KA propeller series and BTKI=0.48 for the case of JD7704 duct + JDC propeller series.

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如上所述，当速度对导管螺旋桨诱导的计算，不同的治疗应用。图给出了比较结果通过两年的治疗，其中“病毒”和“导航”表示圆周平均和不平均，分别。它是从4，推力管lowadvance系数可以改善时，诱导速度螺旋桨导管不圆周平均，即唤醒背后的存在。这一结论是一致的，从参考[ 7 ]。在无花果。5和6，参数btki系数确定水动力螺距角在过渡区之后的螺旋桨。通常btki = 0.5是采用面板方法的单螺旋桨。它可...

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如上所述，当速度对导管螺旋桨诱导的计算，不同的治疗应用。图给出了比较结果通过两年的治疗，其中“病毒”和“导航”表示圆周平均和不平均，分别。它是从4，推力管lowadvance系数可以改善时，诱导速度螺旋桨导管不圆周平均，即唤醒背后的存在。这一结论是一致的，从参考[ 7 ]。在无花果。5和6，参数btki系数确定水动力螺距角在过渡区之后的螺旋桨。通常btki = 0.5是采用面板方法的单螺旋桨。它可以从无花果。5和6 btki = 0.43给出更好的结果的情况下jd7704管+嘉螺旋桨系列和btki = 0.48的情况下jd7704管+型螺旋桨系列。在数值计算方法的实验板面板，醒来的propellerand管被截断在一定距离后面的螺旋桨或管道。图7表明，合理的结果时获得的过渡范围的螺旋桨为1080度。这是发现的图，数值结果成为融合逐渐增加地区的尾涡管，将不会有任何影响的导管推力如果尾管长度的四倍以上的长度管道，将使用以下计算公司。样本表明，收缩系数的过渡的螺旋桨，rw0，不影响计算结果，甚至rw0 = 0.83，0.98或1（“魂斗罗”所示）。rw0 = 0.83是采用本文。

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