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一种水下螺旋桨辐射噪声的建模方法(英文) 被引量:3
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作者 罗昕炜 刘文胜 方世良 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第5期632-639,共8页
基于三参数功率谱曲线(Ecs)模型和自回归(AR)模型的螺旋桨噪声建模方法已经在工程中得到广泛的应用.然而,噪声模型输出的稳定性条件缺乏严格的证明,同时缺乏实测噪声到模型参数的一个有效提取方法,给噪声模型的实际应用带来困难.本文详... 基于三参数功率谱曲线(Ecs)模型和自回归(AR)模型的螺旋桨噪声建模方法已经在工程中得到广泛的应用.然而,噪声模型输出的稳定性条件缺乏严格的证明,同时缺乏实测噪声到模型参数的一个有效提取方法,给噪声模型的实际应用带来困难.本文详细讨论了Ecs模型曲线的性质及其与螺旋桨辐射噪声统计特性的一致性.讨论了噪声模型中的AR模型稳定性条件.首先,利用Schur-Cohn准则将AR模型的稳定性等价为Levinson-Durbin递归计算中所有反射系数绝对值小于1的问题.其次,证明了Yule-Walker方程中的自相关矩阵合同于以各阶建模误差为对角元素的对角阵.根据Sylvester惯性定理,将对反射系数的约束条件等价为自相关矩阵的正定性条件.最后证明了在Ecs模型曲线非负条件下AR模型输出具有稳定性,给出了一种稳定Ecs模型中三个参数的约束条件.此外,本文给出了一种利用实测数据估计Ecs模型参数的方法.首先通过噪声功率谱峰值估计Ecs参数f0,设计Ecs曲线和测量噪声的功率谱曲线的误差函数联合估计fm和λ,最后修正信号的方差.采用缩比四叶螺旋桨模型,设计并开展了一次螺旋桨噪声水池实验,采集了多种转速条件下的螺旋桨辐射噪声.实验数据分析表明,在不同转速条件下,Ecs模型曲线均能较好的逼近实测螺旋桨噪声数据的功率谱谱形.实测数据估计的模型参数与螺旋桨的空化状态表现出较好相关性,可以作为噪声特征参数. 展开更多
关键词 水下螺旋桨 辐射噪声 三参数功率谱曲线模型 参数估计
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水下螺旋桨技术发展现状与展望 被引量:5
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作者 王晓强 龚正琦 《中国水运》 2021年第4期74-76,共3页
本文围绕水下螺旋桨技术,对目前国内外在相关领域的发展进行了总结。主要关注于水下螺旋桨设计技术,螺旋桨计算流体力学(CFD)技术以及水下螺旋桨优化技术三个方面的研究现状,分析了各相关技术的研究特点,并展望了水下螺旋桨相关技术研... 本文围绕水下螺旋桨技术,对目前国内外在相关领域的发展进行了总结。主要关注于水下螺旋桨设计技术,螺旋桨计算流体力学(CFD)技术以及水下螺旋桨优化技术三个方面的研究现状,分析了各相关技术的研究特点,并展望了水下螺旋桨相关技术研究趋势,为进一步研究水下螺旋桨技术提供了参考。 展开更多
关键词 水下螺旋桨 螺旋桨设计 计算流体力学 优化技术
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类空化效应下的水下螺旋桨推进器推力预测 被引量:4
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作者 罗阳 李战东 +2 位作者 陶建国 邓立平 邓宗全 《机械工程学报》 EI CAS CSCD 北大核心 2020年第17期1-11,共11页
类空化效应是由于水下螺旋桨推进器近水面高速旋转时,在螺旋桨与水面之间形成漩涡,从而将空气吸入桨内导致推进器效率极大降低,引起推力损失和噪声的现象。螺旋桨推进器作为大多数水下机器人的唯一动力源,类空化效应的产生将极大影响机... 类空化效应是由于水下螺旋桨推进器近水面高速旋转时,在螺旋桨与水面之间形成漩涡,从而将空气吸入桨内导致推进器效率极大降低,引起推力损失和噪声的现象。螺旋桨推进器作为大多数水下机器人的唯一动力源,类空化效应的产生将极大影响机器人运动控制的稳定性。提出了一种基于高斯过程的水下螺旋桨推进器推力预测方法,可以实现类空化效应下的高精度推力预测。介绍了类空化效应并揭示类空化效应的产生机理。建立了基于贝叶斯估计的推进器推力模型,对未出现空化效应时的推进器推力进行准确预测。在此基础上,提出了基于高斯过程的推进器推力预测模型,利用基于贝叶斯估计的推力预测模型与基于高斯过程的类空化误差补偿,实现对类空化效应下的推力预测。通过试验验证了基于高斯过程的类空化预测模型的精确性与有效性,为水下机器人近水面的高精度运动控制奠定基础。 展开更多
关键词 水下螺旋桨推进器 类空化效应 推力预测 贝叶斯估计 高斯过程
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Numerical Analysis of the High Skew Propeller of an Underwater Vehicle 被引量:3
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作者 Hassan Ghasseni Parviz Ghadimi 《Journal of Marine Science and Application》 2011年第3期289-299,共11页
A numerical analysis based on the boundary element method (BEM) was presented for the hydrodynamic performance of a high skew propeller (HSP) which is employed by an underwater vehicle (UV). Since UVs operate at... A numerical analysis based on the boundary element method (BEM) was presented for the hydrodynamic performance of a high skew propeller (HSP) which is employed by an underwater vehicle (UV). Since UVs operate at two different working conditions (surface and submerged conditions), the design of such a propeller is a cumbersome task. This is primarily due to the fact that the resistance forces as well as the vessel efficiency under these conditions are significantly different. Therefbre, some factors are necessary for the design of the optimum propeller to utilize the power at the mentioned conditions. The design objectives of the optimum propeller are to obtain the highest possible thrust, minimum torque, and efficiency. In the current study, a 5-bladed HSP was chosen for running the UV. This propeller operated at the stern of the UV hull where the inflow velocity to the propeller was non-uniform. Some parameters of the propeller were predicted based on the UV geometrical hull and operating conditions. The computed results include the pressure distribution and the hydrodynamic characteristics of the HSP in open water conditions, and comparison of these results with those of the experimental data indicates good agreement. The propeller efficiency for both submerged and surface conditions was found to be 67% and 64%, respectively, which compared to conventional propellers is a significantly higher efficiency. 展开更多
关键词 boundary element method (BEM) hydrodynamic analysis high skew propeller surface andsubmerged conditions
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Numerical computation and analysis of unsteady viscous flow around autonomous underwater vehicle with propellers based on sliding mesh 被引量:4
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作者 高富东 潘存云 韩艳艳 《Journal of Central South University》 SCIE EI CAS 2012年第4期944-952,共9页
The flexible transmission shaft and wheel propeller are combined as the kinetic source equipment, which realizes the nmlti-motion modes of the autonomous underwater vehicle (AUV) such as vectored thruster and wheele... The flexible transmission shaft and wheel propeller are combined as the kinetic source equipment, which realizes the nmlti-motion modes of the autonomous underwater vehicle (AUV) such as vectored thruster and wheeled movement. In order to study the interactional principle between the hull and the wheel propellers while the AUV navigating in water, the computational fluid dynamics (CFD) method is used to simulate numerically the unsteady viscous flow around AUV with propellers by using the Reynolds-averaged Navier-Stokes (RANS) equations, shear-stress transport (SST) k-w model and pressure with splitting of operators (PISO) algorithm based on sliding mesh. The hydrodynamic parameters of AUV with propellers such as resistance, pressure and velocity are got, which reflect well the real ambient flow field of AUV with propellers. Then, the semi-implicit method for pressure-linked equations (SIMPLE) algorithm is used to compute the steady viscous flow field of AUV hull and propellers, respectively. The computational results agree well with the experimental data, which shows that the numerical method has good accuracy in the prediction of hydrodynamic performance. The interaction between AUV hull and wheel propellers is predicted qualitatively and quantitatively by comparing the hydrodynamic parameters such as resistance, pressure and velocity with those from integral computation and partial computation of the viscous flow around AUV with propellers, which provides an effective reference to the shady on noise and vibration of AUV hull and propellers in real environment. It also provides technical support for the design of new AUVs. 展开更多
关键词 computational fluid dynamics sliding mesh wheel propeller autonomous underwater vehicle viscous flow field
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