Huang Y.,Dalian Ocean University |
Liu D.,Dalian Ocean University |
Sun F.,Dalian Ocean University |
Gao M.,COSCO DALIAN SHIPYARD CO. |
Zhang Y.,Dalian Ocean University
Advanced Materials Research | Year: 2012
The proposal of this investigation is the optimization design of bulbous bow-lines for a container vessel. The results of wave-making coefficients and relative data of wave-making field both from computation based on Green function method and Michell integral method are provided for 7 different designs of bulbous bow lines respectively in this paper. According to the minimum energy from the sample of average wave-making energy for each design of bulbous bow-lines, which is to be objective function in this computation, the geometric parameters for optimization lines of bulbous bow can be determined. Adopting CFD method, it is respectively calculated that the average wave energy change with the ahead extendable length of bulbous bow, the height above the baseline of bulbous bow and the transverse area of the bulbous bow at fore pole. By above three change curves, the optimization shape of the bulbous bow is gained. The resistance components and the wave-field for wave-making for ship hull by using CFD method have been validated based on corresponding model test results. Therefore, the optimized bulbous bow-lines can be used in the ship design practice. © (2012) Trans Tech Publications. Source
Bai X.,Jiangsu University of Science and Technology |
Sun L.,Harbin Engineering University |
Qin W.,Jiangsu University of Science and Technology |
Lv Y.,COSCO DALIAN SHIPYARD CO.
Journal of Marine Science and Application | Year: 2014
The stiffened cylindrical shell is commonly used for the pressure hull of submersibles and the legs of offshore platforms. There are various failure modes because of uncertainty with the structural size and material properties, uncertainty of the calculation model and machining errors. Correlations among failure modes must be considered with the structural reliability of stiffened cylindrical shells. However, the traditional method cannot consider the correlations effectively. The aim of this study is to present a method of reliability analysis for stiffened cylindrical shells which considers the correlations among failure modes. Firstly, the joint failure probability calculation formula of two related failure modes is derived through use of the 2D joint probability density function. Secondly, the full probability formula of the tandem structural system is given with consideration to the correlations among failure modes. At last, the accuracy of the system reliability calculation is verified through use of the Monte Carlo simulation. Result of the analysis shows the failure probability of stiffened cylindrical shells can be gained through adding the failure probability of each mode. © 2014 Harbin Engineering University and Springer-Verlag Berlin Heidelberg. Source
Li Z.-Y.,Harbin Engineering University |
Li Z.-Y.,Dalian University of Technology |
Wang K.-J.,Harbin Engineering University |
Zhang M.-J.,Dalian University of Technology |
Xu L.,COSCO DALIAN SHIPYARD CO.
Kongzhi yu Juece/Control and Decision | Year: 2012
A direct multi-step prediction model based on chaotic and second order diagonal recurrent neural network with two recurrent weights in hidden layer is proposed. A generalized dynamic back-propagation (DBP) algorithm is applied to training, and the convergence of DBP is derived. Simulation results show that, direct multi-step prediction does not depend on the results of single-step prediction, and the proposed network can make a rapid and accurate prediction of the ship rolling time series, and provides more prediction accuracy and more prediction time by comparing to single-step prediction. Source
Huang Y.N.,Dalian Ocean University |
Huang Y.N.,Dalian University of Technology |
Liu D.L.,Dalian Ocean University |
Sun F.S.,Dalian Ocean University |
And 2 more authors.
Applied Mechanics and Materials | Year: 2013
In this paper, with a 92,500 ton bulk-carrier being mainly taken as an example, the preparing design of launching processing scheme on the horizontal berth is discussed. Calculation of needed hulling force and strength examination of hoisting pad are done, and then the structural strength of hoisting pads and their stiffening structures are analyzed with the aid of finite element technique. Once the total assembly of hull is completed on the berth, the launching weight should be calculated and proper number of box-beams should be determined. Sliding frictional media used between box-beams and slipping -rails should be selected, and according to combined frictional coefficient, the needed pulling force by which the hull may be hoisted forward securely should be fixed. In order to assure the safety of ship in the period of launching, strength examination calculating for hoisting pads and stiffening members should be done by means of finite element method as soon as their types and assembling positions are determined, so that the strength of hoisting pads and stiffening structures should be able to meet the requirements. Owing to that this ship having being successfully launched, the reliability and usability stated in this paper have being verified. Therefore, it is of quite value to be referred in technical analysis for launching on the horizontal slipway. © (2013) Trans Tech Publications, Switzerland. Source
Liu Y.,Harbin Engineering University |
c M.,Harbin Engineering University |
Liu S.,COSCO DALIAN SHIPYARD CO.
Journal of Marine Science and Application | Year: 2013
The research study proposes to examine a three-dimensional visualization program, emphasizing on improving genetic algorithms through the optimization of a layout design-based standard and discrete shipbuilding workshop. By utilizing a steel processing workshop as an example, the principle of minimum logistic costs will be implemented to obtain an ideological equipment layout, and a mathematical model. The objectiveness is to minimize the total necessary distance traveled between machines. An improved control operator is implemented to improve the iterative efficiency of the genetic algorithm, and yield relevant parameters. The Computer Aided Tri-Dimensional Interface Application (CATIA) software is applied to establish the manufacturing resource base and parametric model of the steel processing workshop. Based on the results of optimized planar logistics, a visual parametric model of the steel processing workshop is constructed, and qualitative and quantitative adjustments then are applied to the model. The method for evaluating the results of the layout is subsequently established through the utilization of AHP. In order to provide a mode of reference to the optimization and layout of the digitalized production workshop, the optimized discrete production workshop will possess a certain level of practical significance. © 2013 Harbin Engineering University and Springer-Verlag Berlin Heidelberg. Source