Study on Transom Stern Form Design Method Based on a New Theory

1.横梁尾部剖面形状对尾浪阻力的影响(1)尾部剖面形状对尾浪阻力的影响：尾部剖面凹陷使船体在较低航速范围内的尾浪阻力最小。在较高航速范围内，平底剖面产生的尾浪阻力最小。(2)船底剖面形状与尾浪阻力的关系：-在较低航速范围内，船底剖面形状主要通过控制实际尾端浸没来控制尾浪阻力。-在较高船速范围内。3.1，尾底剖面形状主要通过控制剩余跟随波高来控制尾波阻力。-凹的尾底剖面导致最小的实际尾端浸没I_r，这在较低的船速范围内是重要的。平坦的船尾底部剖面导致了最低的剩余波高，这在…很重要(3)船体阻力的相对大小：船底形状变化的影响在全尺寸船舶的动力中估计是显著的。2.航行中尾端浸没对尾浪阻力的影响(1)建立了估算实际尾部浸没I_r对尾浪阻力影响的方法--发展了一种考虑I_r的尾部阻力的解析估算方法。(2)铁对尾波阻力的影响用上述方法对模型试验结果进行分析，得出以下结论：-i_r通过影响尾端水流速度和尾浪高度2~lt而与尾波阻力有关；R0&gt；-在F_&lt；ri&>；&lt；3.1：i_r/i的较低弗劳德数范围内。较大的I_r/I由于尾端水流加速而产生较大阻力，且C_&lt；ACCS&>；在尾浪阻力C_&lt；Sw&gt；中占有较大比例。I_r/I主要通过C&lt；ACCS&gt；影响尾波阻力C&lt；Sw&gt；，因此，尾波阻力几乎由F&lt；ri&gt；和I_r/I决定--在F&lt；ri&gt；&gt；3.1：i&r/i的较高弗劳德数范围内较小。因此，I_r/I对尾浪阻力的影响并不重要。因此，尾浪阻力几乎由F&lt；ri&gt；和θ_e决定。基于上述研究结果，提出了一种作为集装箱船在吃水范围内航行的船的尾部底型设计的理论方法。4.现在的研究计划我们想研究尾波阻力等于0的尾部尾型。这种尾型对于尾型的研究是非常重要的，也是研究尾型所必需的，因为利用尾型可以将尾浪阻力与剩余阻力分离。较少

1.Effect of Transom Stern Bottom Profile Form on Stern Wave Resistance(1)Effect of the transom stern bottom profile form:The concave stern bottom profile causes the lowest stern wave resistance at the lower ship speed range of F_<rI><3.1. The flat stern bottom profile causes the smallest stern wave resistance at the higher ship speed range of F_<rI>>3.1.(2)Relation between Stern Bottom Profile Form and Stern Wave Resistance:-At the lower ship speed rage of F_<rI><3.1, the stern bottom profile form controls the stern wave resistance mainly by controlling the real stern end immersion I_r.-At the higher ship speed range of F_<rI>>3.1, the stern bottom profile form controls the stern wave resistance mainly by controlling the remaining following wave height.-The concave stern bottom profile causes the smallest real stern end immersion I_r which is important at the lower ship speed range. The flat stern bottom profile causes the lowest remaining following wave height which is important at th … More e higher ship speed range.(3)Relative amount of the effect in hull resistance:Amount of the effect of the stern bottom form change is estimated to be significant in the powering for a full-scale ship.2.Effect of I_r(stern end immersion at running) on Stern Wave Resistance(1)Development of a method to estimate the effect of real stern immersion I_r on the stern wave resistance-An analytical method to estimate the stern wave resistance due to a transom stern taking I_r into consideration has been developed.-In the method, the stern wave resistance is treated as consisting of the four components : that due to the swbf, that due to the rfw, that due to acceleration of water flow at the stern end and that due to static water pressure change on the stern end plane.(2)Details of the effect of Iron the stern wave resistanceAnalysis of the model test results with above developed method has clarified the followings:-I_r relates with the stern wave resistance through its affecting the water flow velocity at the stern end viand the stern wave height 2_<r0>.-At the lower Froude number range of F_<rI><3.1:I_r/I is larger. The larger I_r/I brings larger resistance due to acceleration of water flow at the stern end C_<accs> and the C_<accs> occupies larger part of the stern wave resistance C_<sw>. I_r/I affects the stern wave resistance C_<sw> mainly through the C_<accs> The stern wave resistance is, therefore, almost decided by F_<rI> and I_r/I.-At the higher Froude number range of F_<rI>>3.1:I_r/I is smaller. The effect of I_r/I on the stern wave resistance is, therefore, not important. The stern wave resistance, the main part of which is the resistance due to the rfw C_<sfw>, is accordingly almost decided by F_<rI> and θ_e.3.Development of a Transom Stern Bottom Profile Form Design MethodBased on the results of the study described above, an theoretical method to design bottom profile form of the transom stern for such a ship that runs over a range of draft as a container ship has been proposed.4.Study Plan from NowWe would like to study on such a transom stern form of which stern wave resistance is equal to 0. Such a transom stern form is practically important and also necessary for study of transom stern form, because the stern wave resistance can be isolated from the residual resistance by using the transom stern form. Less