Tian Z.-D.,Beijing West Third Ring Road19 A 4 |
Ji F.,Harbin Engineering University |
Ji F.,China Ship Research and Development Academy
Chuan Bo Li Xue/Journal of Ship Mechanics | Year: 2011
Based on wave theory, the characteristics of wave propagation of typical hull structure from blocking mass are discussed. Concerned with assemble process, the influence of eccentricity of blocking mass to its vibration isolation performance is analyzed. From the engineering application point of view, the blocking mass ribbon is introduced into rigid vibration design of typical base structure. Combining the acoustic-structural coupled method and Statistical Energy Analysis, the full-band influences of blocking mass ribbon cross-section size, cross-section shape parameters and layout location to base isolation performance are discussed. On this base, the quick-engineering prediction method of base blocking mass ribbon in power cabin is developed, which aims to provide reference for primary acoustic design of typical hull structure.
Liu S.,Harbin Engineering University |
Cheng Y.,China Ship Research and Development Academy
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2015
In order to solve the problem that the generation system with constant power loads can result in voltage instability in shipboard medium voltage DC integrated power systems, small signal model based eigenvalue stability analysis was employed in this paper. A constant RL-branch synchronous generator voltage-behind-reactance (VBR) model combining diode rectifier average value model modeling approach was proposed. Low pass filters are employed to solve the problem that the system can not be conducted in ordinary differential equation (ODE) form directly, and the nonlinear ODE model for the generation system was constructed. The model was validated by detailed numerical simulation. Based on the ODE model, the small signal model was constructed and the stability of the generation system was analyzed by the eigenvalue loci of equilibrium points. The stability of the system with different inputs and design parameters was investigated, and the stability regions were obtained. The results of the stability analysis were validated by both the quantitative simulation and qualitative analysis. © 2015 Chin. Soc. for Elec. Eng.
Zheng M.,China Ship Research and Development Academy
Wuhan Ligong Daxue Xuebao/Journal of Wuhan University of Technology | Year: 2015
To determine the angle and position in width direction of angled deck objectively, this paper reviewed and analyzed the factors that influence the angled deck general arrangements. Based on several schemes of foreign mature aircraft carriers, support vector machine (SVM) model was introduced to regression and gain the trand and characteristics of angled deck arrangement. The regression for former Soviet Union Ulyanovsk aircraft carrier demonstrates that the accuracy and validity of this method is good. © 2015, Wuhan University of Technology. All right reserved.
Pan D.-Y.,Zhejiang University |
Liu H.,China Ship Research and Development Academy |
Shao X.-M.,Zhejiang University
Journal of Hydrodynamics | Year: 2010
This paper studies the oscillation behavior of a flexible plate in the wake of a D-section cylinder. The interaction between the flexible body and its surrounding vortices is investigated. A modified immersed boundary method is used to solve the motion of fluid, integrated with a linearized Euler-Bernoulli beam model to govern the motion of the flexible plate. Results show that, when the distance between cylinder and plate is small, the surface of the plate is surrounded by vortices layers and the plate oscillates periodically, with amplitude similar to the cylinder movement. However, if the distance becomes large, we find that the vortices are shed from the D-cylinder in front of the plate, and the incoming vortices make the plate oscillate with large amplitude at the beginning and then slant laterally. Also, the amplitude becomes smaller compared to the case of the small distance. © 2010 Publishing House for Journal of Hydrodynamics.
He C.,Northwestern Polytechnical University |
Huang J.,Northwestern Polytechnical University |
Yan Z.,China Ship Research and Development Academy |
Zhang Q.,Northwestern Polytechnical University
Science China Information Sciences | Year: 2011
A novel M-ary code division multiple access (M-ary CDMA) underwater acoustic communication (UAC) that utilizes quasi-orthogonal sequences has been proposed for the multiple mobile unmanned underwater vehicle (UUV). Its performance has been verified in both four-user synchronous and three-user asynchronous scenarios through a lake experiment over a very shallow-water channel. At a chip rate of 2 kilochips per second, good bandwidth efficiency and robust links have been achieved both at 5 and 15 km distances. The performance of M-ary CDMA in mobile condition (3 m/s) is demonstrated by using the recorded lake experimental data. Experimental results show that the proposed scheme is suitable for multi-user communication platform in long-range shallow-water channel with simple receiver algorithms. © 2011 Science China Press and Springer-Verlag Berlin Heidelberg.