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Beijing, China

Cao J.,Wuhan Naval University of Engineering | Cao J.,Naval Arming Academy | Wei Z.,Wuhan Naval University of Engineering | Liu S.,Wuhan Naval University of Engineering
Zhendong Ceshi Yu Zhenduan/Journal of Vibration, Measurement and Diagnosis | Year: 2013

A new method of modal parameter identification based on second-order blind source separation improved by quantum genetic algorithm is proposed. Firstly, Hilbert transformation of the measured data is used to build data analysis matrix. After the optimal delay from quantum genetic algorithm, joint approximate diagonalization of the optimal delay second-order covariance matrix is used to separate the mixed signals. Then modal shapes are extracted from the mixed matrix. Finally, frequency and damping ratios could be obtained from the modal responses using each single degree of freedom mode. Experimental results of steel structure prove that the proposed method is applicable in complex modal case. Furthermore, the method possesses the advantages of simplified calculation and high identification accuracy.

Zhang W.,Naval Arming Academy | Zhang W.,Chinese Naval Aeronautical Engineering Academy
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2010

Heavyweight shipboard equipments must be tested on a floating shock platform(FSP), however, the shock test is time-consuming, laborious and expensive. The finite element modeling and simulation can provide a viable and cost effective alternative to shock tests. The objective of the paper is to examine the response of shipboard equipment on a floating shock platform(FSP) using nonlinear ABAQUS finite element software. The results can provide a reference for the evaluation of shipboard equipment's shock resistivity and the design of large FSP.

Wang Y.,Naval Arming Academy | Ji C.,Naval Arming Academy | Ji C.,Wuhan Naval University of Engineering | Du J.-Y.,Naval Arming Academy | Zhu C.-S.,Zhejiang University
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2011

The types of shock impulse of ship shafting systems were introduced. Shock dynamic model of a ship shafting system was built with finite element method, and a software (SHAFTFE) for ship shafting system dynamics and shock response simulation was developed with MATLAB. Dynamic characteristics of a ship power shafting system including propulsion shafting, propulsion electric motor and its vibration isolator were analyzed using SHAFTFE with different shock forces and parameters, and effects of the structural design parameters of the ship shafting system on the shock response were analyzed. The results showed that the ship power shafting system has a larger displacement under the action of the base shock, so more attention must be paid to the shock character of ship power shafting systems during design in order to increase reliability and survival performance of a whole ship.

Ji C.,Naval Arming Academy | Ji C.,Wuhan Naval University of Engineering | Wang Y.,Naval Arming Academy | Yang L.,Naval Arming Academy | Feng L.-H.,Naval Arming Academy
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2011

Considering the shock-resistance threshold of equipment on board as the important base for ship shock-resistance design and assessment, a finite element model of marine gearbox was established to get the characteristic of shock-resistance threshold. The shock-resistance threshold was analyzed using endurable stress method. Results indicate that endurable stress method is a direct and effective computational method for getting shock-resistance threshold of marine equipment. The shock-resistance threshold of marine gearbox is related to the peak value of acceleration and pulse width of input load.

Ji C.,Naval Arming Academy | Ji C.,Wuhan Naval University of Engineering | Wang Y.,Naval Arming Academy | Yang L.,Naval Arming Academy | Feng L.-H.,Naval Arming Academy
Binggong Xuebao/Acta Armamentarii | Year: 2011

Considered many non-linear contact relationships between the main components in diesel, a time domain simulation method was applied to assessment its shock response. In the assessment, some modeling principles of complex mechanical systems, such as diesel, were given. Also, the finite element models of main components in V6 diesel were established, and then, their shock response characteristics were analyzed in time-domain on the basis of BV043/85 criterion. The stress responses of main components showed the shock vulnerability spots, and the motion response and results of oil film on bearing indicated the work ability. Theanalysis results show that the assessed diesel meet BV043/85 standard on impact security level of A-grade equipments.

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