【作者】 胡健；

【导师】 黄胜；

【作者基本信息】 哈尔滨工程大学 ， 船舶与海洋结构物设计制造， 2006， 博士

【摘要】 随着现代水下声探测技术的发展，舰船声隐身性能成为造船界普遍关注的问题。其中，作为舰船三大噪声源之一的螺旋桨空泡噪声已受到越来越多的关注，本文从理论和实验两个方面系统地研究螺旋桨的空泡噪声，并建立了以降噪为目的的螺旋桨优化设计方法。在船尾非定常流动中工作的螺旋桨，常常由于桨叶负荷过大而产生空泡，从而引起强烈的辐射噪声，降低舰船的隐身性能，为了降低空泡螺旋桨的辐射噪声，必须从螺旋桨设计入手，在额定工作状态下，避免或延缓空泡的发生。增加螺旋桨空泡斗的宽度，控制空泡发生的范围，尽量避免泡状空泡的发生。论文分析了国内外螺旋桨辐射噪声的技术特点，详细地介绍了螺旋桨空泡噪声的研究现状，分析了低噪声螺旋桨设计中存在的问题和解决策略，从降低螺旋桨的关键技术入手，提出了低噪声螺旋桨的优化设计方法。论文用理论方法系统地研究了均匀流场和非均匀流场中的螺旋桨的性能预报问题，并编制了相应的数值程序，其中包括螺旋桨定常水动力性能预报和螺旋桨非定常水动力性能预报。用基于速度势的低阶面元法预报了螺旋桨的定常水动力性能。由格林公式推导出该问题的积分方程；用物面不可穿透条件、无穷远条件、库塔条件等作为方程的定解条件；螺旋桨的非定常水动力性能采用时域方法求解，为了减少计算时间和降低计算机的存储量，论文采用了主桨叶方法，其他桨叶上的未知量均可由主叶片按一定相位角推算，在计算的每一时间步长的计算方法基本上与定常时相同。论文用面元法预报了螺旋桨的空泡性能，包括空泡的长度、厚度、体积等。用格林公式导出该问题的积分方程，运动学边界条件、动力学边界条件、无穷远条件、库塔条件等作为方程的定解条件，理论计算结果和试验结果吻合良好。论文同时对螺旋桨的空泡问题进行了试验研究，用实验手段记录了螺旋桨空泡的发生、发展等过程，并将其作为螺旋桨空泡性态预报的校核依据，最后论文用仿真软件对非定常流动中螺旋桨的空泡形态进行了模拟，可以更直观讨论非均匀流动中螺旋桨空泡性态的变化过程。论文讨论了不同参数对螺旋桨空泡性能的影响，并建立了低噪声螺旋桨的优化设计方法，以面元法作为基本的数值方法，用样条曲面模拟螺旋桨表面形状，当螺旋桨在非均匀流场中运转时，根据桨叶表面的压力分布在数值程序中自动调整样条曲面的基函数，使得桨叶表面的压力分布更为平均，同时尽量增大桨叶表面的最小压力，避免或延缓空泡的发生。试验表明，用该方法设计的螺旋桨辐射噪声比母型桨有明显的降低。更多还原

【Abstract】 With the development of underwater detective equipment, ship acoustic stealthy technique becomes a popular problem within shipbuilding researcher. Thus, propeller cavitation radiated noise as one of three primary noise source has drawn more and more attention. The paper mainly investigates propeller cavitation noise from theoretical aspect and experimental aspect, and establishes a optimization design method for the aim to reduce propeller cavitation radiated noise.When a propeller works in the unsteady inflow behind stern, transient cavitation will appear, and bring down the ship stealthy performance because of the induced considerable radiated noise. For the purpose to decrease the cavitation radiated noise, it’s necessary to delay or void the appearance of cavitation when a propeller is designed. A wider bucket is effective to improve the cavitation performance of a propeller.The dissertation analyzes the technology features of cavitation radiated noise, introduces current technology situation of cavitation noise. From the key technologies to reduce the cavitation noise, The dissertation establishes a optimization design method for the purpose to reduce propeller cavitation radiated noise.The dissertation investigates the hydrodynamic performance of the propeller with theoretical method, and compiles the corresponding numerical program, which includes steady hydrodynamic performance prediction and unsteady hydrodynamic performance prediction. Steady hydrodynamic performance prediction is solved with low-order panel method based on velocity potential, the integral equation is derived from Green formula, the border condition including rigid object condition, the far distance condition and Kutta condition. Unsteady hydrodynamic performance prediction is solved by time domain method. The dissertation uses key blade method to reduce the computing time , the unknown parameters of other blades are derived from the key blade by the corresponding phase angle. At every time step a linear algebraic equation established on a key blade is solved numerically combined with the Kutta pressure condition.The dissertation predicts the propeller cavitation shape, including cavitation extent, cavitaiton thickness and volume, the integral equation is derived from Green formula, the solution condition including kinematic condition, dynamic condition, rigid object border condition, the far distance condition and Kutta condition. calculation results are in good agreement with the experimental data. The dissertation analyzes the cavitation problem with experimental method, notes the transient process as the foundation of verification foundation of mathematical method. The dissertation simulates the transient process of cavitation with software, so it’s more clearly to analyze the movement of cavitation.The dissertation discusses the effect of different parameters on propellercavitation performance, and develops an optimization design method for the purpose to reduce propeller cavitation radiated noise. Use panel method as the basic numerical method, adopt spline surface to simulate the shape of blades. When the propeller rotates in the unsteady inflow, the spline function is adjusted according to the pressure distribution of blade section. So the thickness distribution and camber distribution of blade section are adjusted to get a smooth pressure distribution. As well, the minimum pressure is increased to delay the emergence of cavitation. The experiment shows that the design propeller has a lower cavitation noise than the original propeller.更多还原