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可调螺距螺旋桨水动力性能分析 总被引:5,自引:2,他引:3
利用面元法分析可调距螺旋桨的水动力性能.计算过程中,采用较为简捷的关于扰动速度势的基本积分微分方程,并采用双曲面形状的面元以消除面元间的的间隙,Newton-laphson迭代过程被用来在桨叶随边满足压力Kutta条件,使桨叶上下表面的的压力在随边有良好的一致性,同时用模拟物体真实行状的面元法来解决调距桨在螺距变化时的叶剖面畸变的问题.用Morino导出的解析计算公式来计算面元的影响系数,加快了数值计算的速度.以无厚度线性尾涡模拟桨叶泄出涡.调距螺旋桨最佳转轴位置由理论方法求出,使得桨叶的转叶矩为零.计算过程中计入了桨毂的影响,并分析了桨毂对桨叶表面压力分布的影响.最后给出了调矩螺旋桨水动力性能随随螺距的变化规律,并和试验结果作了比较分析. 相似文献
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基于流固耦合的螺旋桨性能分析及参数优化 总被引:1,自引:0,他引:1
为了研究某型螺旋桨水动力及强度特性.首先建立螺旋桨实体模型,再在CFX中设置计算条件,运用CFD有限元方法计算与分析不同进速下螺旋桨的推力系数、转矩系数、敞水效率以及桨叶压力分布等水动力参数特性及其变化趋势;然后通过Workbench平台应用流固耦合方法,将CFX求解得到的螺旋桨表面压力载荷加载到螺旋桨结构强度分析模型上,对螺旋桨的强度进行计算.最后通过改变纵倾角和螺距对螺旋桨结构进行优化,并将仿真结果与原桨比较,结果表明适当增大纵倾角能增大螺旋桨强度,适当降低螺距能提高螺旋桨敞水效率、提高抗空泡性能并增大螺旋桨强度. 相似文献
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螺旋桨水动力性能的数值预报方法 总被引:1,自引:0,他引:1
基于速度势的低阶面元法预报螺旋桨的水动力性能。选用四边形双曲面元对桨叶进行离散以消除面元间的缝隙,基本积分方程由格林公式导出。在面元上布置等强度源汇和偶极子。采用线性尾涡并在每个尾涡面元上布置等强度的偶极子。利用Newton-Raphson迭代过程满足桨叶随边非线性等压kutta条件,使桨叶上下表面的压力在随边处一致。利用Morino计算影响函数的解析公式,采用Yanagizawa方法求得物体表面上的速度分布,并对普通桨和大侧斜桨进行了数值预报。 相似文献
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运用CFD方法中的汽-液混合二相流模型模拟JDC4-55可调桨的水动力性能和空泡性能。通过改变进速和调节桨叶角度得到相应的水动力性能参数。分析空泡对螺旋桨水动力性能的影响,进行JDC4-55可调桨桨流场模拟分析。相对于单相流模型而言,JDC4-55可调桨汽-液混合二相流模型性能计算结果与实验值吻合得更好。 相似文献
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SU Yu-min HUANG ShengCollege of Shipbuilding Engineering Harbin Engineering University Harbin China 《船舶与海洋工程学报》2002,1(1):9-15
The potential based low order surface panel method is used to predict the hydrodynamic performance of marine propellers. In present method the hyperboloidal quadrilateral panels are employed to avoid the gap between the panels. The influencecoefficients of panels are calculated by Morino's analytical formulations for increasing numerically calculating speed.The pres-sure Kutta condition is satisfied on the trailing edge of propeller blade by Newton-Raphson iterative procedure.Therefore the 相似文献
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Michio Ueno Yasuo Yoshimura Yoshiaki Tsukada Hideki Miyazaki 《Journal of Marine Science and Technology》2009,14(4):469-484
Circular motion test data and uncertainty analysis results of investigations of the hydrodynamic characteristics of ship maneuvering
are presented. The model ships used were a container ship and two tankers, and the measured items were the surge and sway
forces, yaw moment, propeller thrust, rudder normal and tangential forces, pitch and roll angles, and heave. The test parameters
were the oblique angle and yaw rate for the conditions of a hull with a rudder and propeller in which the rudder angle was
set to zero and the propeller speed was set to the model self-propulsion conditions. Carriage data showing the accuracy of
the towing conditions in the circular motion test are also presented. It was confirmed that the uncertainties in the hydrodynamic
forces such as the surge and sway forces, yaw moment, rudder tangential and normal forces, and propeller thrust were fairly
small. The reported uncertainty analysis results of the circular motion test data may be beneficial in validating data quality
and in discussing reliability for simulation of ship maneuvering performance. 相似文献
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Hassan GHASSEMI 《船舶与海洋工程学报》2009,8(4):267-274
Demand for high-speed marine vehicles (HSMVs) is high among both commercial and naval users. It is the duty of the marine
vessel’s designer to provide a hull and propulsion system that diminishes drag, improves propulsive efficiency, increases
safety and improves maneuverability. From the propulsor side, surface piercing propellers (SPPs) should improve performance.
Unlike immersed propellers, behavior of the SPP is affected by depth of immersion, Weber number and shaft inclination angle.
This paper uses a practical numerical method to predict the hydrodynamic characteristics of an SPP. The critical advance velocity
ratio is derived using the Weber number and pitch ratio in the transition mode, then the potential based boundary element
method (BEM) is used on the engaged surfaces. Two models of three and six-bladed SPPs (SPP-1 and SPP-2) were selected and
some results are shown. 相似文献
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竖轴水轮机作为潮流能转换为电能的核心装置,其水动力性能的优劣将会直接影响到整体发电系统的效率。为了研究大型竖轴水轮机叶片安装角对水轮机水动力性能的影响,基于多参考系模型(MRF),采用Fluent软件对流场中的模型进行3D数值模拟。在转速和来流速度保持不变,改变安装角时,分析同种翼型5个不同安装角叶片对潮流能水轮机的水动力性能的影响。同时分析在同一安装角和旋转速度条件下,不同来流速度对水轮机水动力性能的影响。结果表明,叶片安装角对竖轴潮流水轮机的能量利用率影响较大,来流速度对水轮机叶片表面的静压力和输出功率具有一定的影响。研究结果对今后竖轴水轮机的设计和生产具有借鉴意义。 相似文献
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采用一种改进的面元法预报螺旋桨水动力性能,将桨叶和桨毂表面离散为四边形双曲面元,每个面元上布置等强度的源,拱弧面和尾涡面离散为布置涡的四边形双曲面元。通过控制点的物面条件求取奇点强度,进而得出桨叶压力分布以及螺旋桨敞水性能,与试验结果比较,计算结果令人满意。 相似文献
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HUANG Sheng WANG Pei-sheng HU Jian 《船舶与海洋工程学报》2007,6(2):6-11
The hydrodynamic performance of a propeller in unsteady inflow was calculated using the surface panel method. The surfaces of blades and hub were discreted by a number of hyperboloidal quadrilateral panels with constant source and doublet distribution. Each panel's corner coordinates were calculated by spline interpolation between the main parameter and the blade geometry of the propeller. The integral equation was derived using the Green Formula. The influence coefficient of the matrix was calculated by the Morino analytic formula. The tangential velocity distribution was calculated with the Yanagizawa method, and the pressure coefficient was calculated using the Bonuli equation. The pressure Kutta condition was satisfied at the trailing edge of the propeller blade using the Newton-Raphson iterative procedure, so as to make the pressure coefficients of the suction and pressure faces of the blade equal at the trailing edge. Calculated results for the propeller in steady inflow were taken as initialization values for the unsteady inflow calculation process. Calculations were carried out from the moment the propeller achieved steady rotation. At each time interval, a linear algebraic equation combined with Kutta condition was established on a key blade and solved numerically. Comparison between calculated results and experimental results indicates that this method is correct and effective. 相似文献
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重点研究了升力鳍升力及转矩与鳍角的非定常水动力特性。通过对鳍升力和转矩的非定常水动力特性试验数据的分析,提出了升力鳍系统的鳍角与升力的换算关系应建立在非定常水动力的基础上。以Theodorsen理论为基础,利用水动力试验数据,修正了基于Theodorsen理论的计算升力系数的公式,提出了修正的升力转矩非定常水动力的数学模型,经实例计算仿真结果与水池试验结果比较,验证了该数学模型的正确性。利用该数学模型直接计算升力,可以省去复杂的、可靠性低、误差大的升力测量装置及复杂的升力计算。该研究也进一步充实了升力鳍非定常水动力特性的理论研究,解决了升力计算的问题。 相似文献
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轮缘推进器作为一种新型的推进方式,取消了螺旋桨推进中轴系的设置,具有舱容占比小、噪声低和振动小等优点,可用于潜艇、鱼雷或者是游艇等海洋航行器,有广泛的应用前景。本文基于STAR-CCM+仿真软件,针对推进器流场进行数值模拟,采用SST k-ω模型完成对轮缘推进器水动力性能的数值计算,分析了建模时简化推进器驱动环间隙及桨叶弦长和螺距比对推进器水动力性能的影响。 相似文献