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建立滑行艇和翼滑艇在正横规则波中的二阶线性横摇运动微分方程,并利用前苏联中央流体动力中心ЦАГИ法得到艇体阻力,利用仿真工具Matlab/Simulink建立滑行艇和翼滑艇的横摇运动、阻力及推进系统的综合仿真模型,仿真计算结果表明建立的横摇运动微分方程较为合理,并验证具有前置V型割划式水翼的翼滑艇其横摇自稳特性要比同等吨位的滑行艇优良许多。 相似文献
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选择具有浅V滑行面及T型水翼11.8m翼滑艇进行阻力研究。进行了翼滑艇模型的阻力实验。选择两个不同的初始安装角(-1.5o及0o),分别进行阻力实验,然后对结果进行综合分析与比较,得到了该型翼滑艇阻力性能的有关结果,纵倾状态随航速的变化情况,以及不同水翼安装角对阻力性能的影响。实验结果表明该船型在高速阶段阻力性能优于尺度相近滑行艇,水翼的设计基本符合要求。实验结果可应用于实船的设计。 相似文献
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基于水动力分析的高速滑行艇阻力估算 总被引:1,自引:0,他引:1
针对滑行艇高速航行的运动特性进行其动态阻力的估算研究。首先通过分析滑行艇在高速航行时艇体受到的各种水动力,建立其六自由度操纵性数学模型,并利用四阶龙格一库塔法解算滑行艇的运动姿态。然后计算滑行艇高速航行时的动态阻力,所得结果与船模试验数据吻合较好,并对各种滑行阶段的运动特性进行分析,结果表明基于水动力分析的阻力估算方法具有较强的工程实用性。 相似文献
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双体滑行水翼艇是一种集双体滑行艇和水翼艇为一体的复合型高速艇,通过双体船增加艇自身横向稳性及其耐波性。在双体滑行艇两片体内侧增设滑行水翼面,在运动过程中,航速达到一定值后,水翼的水动效应为艇体提供一定的升力,使艇体上升,减小艇底湿面积及其阻力,使双体滑行艇阻力大大降低。双体滑行水翼艇兼备了双体滑行艇和水翼艇两者优点,双体滑行水翼艇综合解决了高速艇稳性和快速性问题,使艇的技术性能得到很大的提高。 相似文献
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本文提供了一种水翼艇静水翼航性能的计算方法。本方法根据首尾单独水翼模型试验资料、水翼系统的干扰特性、几何条件和艇的平衡方程组等,借助电子计算机计算水翼艇在整个翼航范围内(包括起飞状态)的航行状态、阻力及推力等性能曲线。问题的关键之一在于准确地估计首水翼对尾水翼水动力性能的干扰效应。作者运用水翼升力线理论的某些结果导出了常用形式水翼系统尾翼处的平均液面下降和平均下洗角的计算公式,并以此计算值来修正尾翼的工作状态。实例计算结果和试验结果是一致的。 相似文献
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滑行艇水动力计算的目的是估算艇的水动力阻力。滑行艇以排水状态航行时,其水阻力计算基本上与普通的排水航行船只相同。但当它起飞后滑行于水的自由表面上,仅部分艇底与水面接触,从而支承面和浸湿面积随速度增长而减少。此时,适用于排水航行船只的阻力计算方法对滑行艇已不适用。 相似文献
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水气双重介质共同作用下可控水翼滑行艇纵向运动预报 总被引:1,自引:0,他引:1
为了探究水气双重介质共同作用下可控水翼滑行艇的运动响应,本文基于喷水推进滑行艇的高速运动原理,建立了水气双重介质共同作用下可控水翼滑行艇非线性纵向运动数学模型。分析了在水气双重介质共同作用下可控水翼滑行艇滑行过程中的受力特性,确定了艇体受到的重力、浮力、动升力、水翼的升阻力及力矩等。提出了可控水翼对滑行艇运动过程中的升沉量和纵倾角的控制策略。完成了0~8级线性风、周期风、随机风作用下水翼变攻角和水翼变攻角+纵向运动对滑行艇运动升沉量和纵倾角控制结果分析。结果表明,当主机输出功率一定时,水翼变攻角可以控制滑行艇的升沉量,弱化纵倾角幅度,而水翼变攻角+纵向运动可以同时控制滑行艇的升沉量和纵倾角。本文为水气双重介质共同作用下可控水翼对滑行艇纵向运动预报提供了有效的研究方法。 相似文献
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消波水翼和压浪板对高速圆舭艇航态与阻力的影响 总被引:1,自引:0,他引:1
应用大展弦比滑行面理论和近水面短翼理论建立了安装在高速圆舭艇上的消波水翼、压浪板升力计算方法,据此研究了消泼水翼、压浪板引起的艇航态变化及其对阻力的影响。理论计算结果与模型试验结果的比较验证了所提计算方法的实用性。 相似文献
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水翼(机翼)的反设计一直是人们研究的热门课题,本文对定常反问题进行了研究.将翼型NACA2412作为计算对象.首先给出翼型的下半部形状,以及上表面的从正问题中计算出来的速度分布.在变分原理的基础上,用有限元方法对水翼进行了数值计算.结果表明,本文理论正确,方法可行. 相似文献
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由于空泡计算的复杂性,国内外以前计算螺旋桨空泡时大多采用的是Morino's Kutta条件,但严格来说,Morino's Kutta只适用二维问题,对三维水翼和螺旋桨空泡的计算会带来一定误差,而等压Kutta条件用Newton-Raphson迭代过程,确保在螺旋桨随边上下表面的压力相等,可以消除Mofino's Kuaa条件所带来的误差,提高空泡在梢部的预报精度.文中用等压Kutta条件预报了三维水翼和螺旋桨的片空泡,并将两种Kutta条件得到的计算结果同试验结果进行了比较. 相似文献
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In the present study, a new approach is applied to the cavity prediction for two-dimensional(2D) hydrofoils by the potential based boundary element method(BEM). The boundary element method is treated with the source and doublet distributions on the panel surface and cavity surface by the use of the Dirichlet type boundary conditions. An iterative solution approach is used to determine the cavity shape on partially cavitating hydrofoils. In the case of a specified cavitation number and cavity length, the iterative solution method proceeds by addition or subtraction of a displacement thickness on the cavity surface of the hydrofoil. The appropriate cavity shape is obtained by the dynamic boundary condition of the cavity surface and the kinematic boundary condition of the whole foil surface including the cavity. For a given cavitation number the cavity length of the 2D hydrofoil is determined according to the minimum error criterion among different cavity lengths, which satisfies the dynamic boundary condition on the cavity surface. The NACA 16006, NACA 16012 and NACA 16015 hydrofoil sections are investigated for two angles of attack. The results are compared with other potential based boundary element codes, the PCPAN and a commercial CFD code(FLUENT). Consequently, it has been shown that the results obtained from the two dimensional approach are consistent with those obtained from the others. 相似文献
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In the present study, a new approach is applied to the cavity prediction for two-dimensional (2D) hydrofoils by the potential based boundary element method (BEM). The boundary element method is treated with the source and doublet distributions on the panel surface and cavity surface by usethe of the Dirichlet type boundary conditions. An iterative solution approach is used to determine the cavity shape on partially cavitating hydrofoils. In the case of a specified cavitation number and cavity length, the iterative solution method proceeds by addition or subtraction of a displacement thickness on the cavity surface of the hydrofoil. The appropriate cavity shape is obtained by the dynamic boundary condition of the cavity surface and the kinematic boundary condition of the whole foil surface including the cavity. For a given cavitation number the cavity length of the 2D hydrofoil is determined according to the minimum error criterion among different cavity lengths, which satisfies the dynamic boundary condition on the cavity surface. The NACA 16006, NACA 16012 and NACA 16015 hydrofoil sections are investigated for two angles of attack. The results are compared with other potential based boundary element codes, the PCPAN and a commercial CFD code (FLUENT). Consequently, it has been shown that the results obtained from the two dimensional approach are consistent with those obtained from the others. 相似文献
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The primary objective of this paper is to present cavitation tunnel tests performed on an optimised shape-adaptive composite hydrofoil and compare the results to other composite hydrofoils. The optimised composite hydrofoil was designed based on prior literature and was manufactured using an optimised ply orientation schedule and a pre-twist. In the same experiment schedule a composite hydrofoil that has a ply orientation that is opposite to the optimised hydrofoil was also tested. In addition to the cavitation tunnel experiments, the paper also presents results predicted from FEA and CFD simulations for the optimised hydrofoil and compares the results from numerical methods to experiments. The results show that the optimised hydrofoil has an improved L/D ratio and a delayed stall phenomenon compared to other hydrofoils. Furthermore, due to the pre-twisted optimised geometry, the hydrofoil does not suffer from loss of lift at low angles of attack. The experimental results demonstrated the importance of characterising the performance of flexible shape-adaptive hydrofoils based on the actual velocity of the flow in addition to the conventional characterisation based on Reynold's number. Additional numerical simulations were performed to investigate the hydrofoils observed load dependant deformation behaviour. These results clearly show that for the same Reynold's number, the hydrofoil can have an appreciably different response if the flow velocity is different. 相似文献
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近水面水翼的兴波由升力线的自由面兴波来表达,船体的兴波考虑升力线兴波的干扰影响,三维时域格林函数法用于船体的兴波分析计算.以Wigley船型为数值计算例,考虑近水面水翼的影响,分别对单体船和双体船进行了船舶兴波计算研究,提供了兴波波形和兴波阻力的计算结果.以系列60船型为数值计算例,把计算的结果与发表的有关结果进行对比,具有较好的吻合.本文还对船舶自由表面兴波波形进行了时域数值仿真. 相似文献
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为了提高水翼艇纵向运动控制的鲁棒性,采用MIMO闭环增益成形算法设计了鲁棒控制器.给出了水翼艇纵向运动传递函数形式的数学模型,通过镜像映射方法将不稳定模型转换成稳定的数学模型.仿真结果表明,所设计的鲁棒控制器将纵摇角降至了原来的25%并对模型摄动具有鲁棒性. 相似文献