Chinese Journal of Ship Research is supervised by China Shipbuilding Industry Corporation (CSIC) and sponsored by China Ship Development and Design Center (CSDDC). The journal is a notable academic journal in the field of naval architecture, shipbuilding and marine engineering in China. It aims to push forward theoretical innovation and advanced technologies. Its scope covers the latest technological breakthroughs, trends, concepts, and discoveries related to the marine industry, naval architects and marine engineering.
The journal is included in CSCD.
Honorary Chairmen AI Ting-yuan, SHAO Kaiwen, WANG Jianguo
Chairman WU Xiaoguang
Vice Chairmen CAI Daming, LIN Zhongqin, MIAO Yu, SHAO Xinyu, WANG Zili, XIA Guihua, XU Qing, ZHANG Qingjie
Invited members DING Rongjun(member of CAE), GONG Xianyi(member o
[Objectives] For the ship structures subjected to pulse loading such as explosion or slamming, research on the “saturated impulse” phenomenon shows that designing hull structures with maximum loading amplitude and total impulse is unreasonable. Hence, exploring the application of saturated impulse in engineering is necessary. [Methods] The concept and development of the saturation phenomenon are first summarized. Then, with a cabin internal explosion as a typical example, the loading curve and structural response characteristics are analyzed by FEM. Following that, the complex blast loadings are equivalent to the rectangular pressure pulse loadings of the saturation equivalent method, and the response of structures under the equivalent loadings is calculated by theoretical and numerical methods. [Results] The results show that the saturated impulse phenomenon exists in a wide array of cabin explosions due to the existence of quasi-static overpressure. In practical engineering problems, the explosion loading will produce large plastic deformation (usually more than 10 times the plate thickness), with an error of less than 10% between the analysis results and the numerical simulation results, by using the equivalent method based on saturated impulse. [Conclusions] By studying the saturation phenomenon of cabin internal explosion, we can give the results of the plastic dynamic response of the structure more accurately, and repeated complex nonlinear numerical calculations can be reduced in structural optimization, so as to carry out the anti-impact design of the hull structure more effectively.
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Objectives] In order to study the damage characteristics of a typical cabin explosion load on stiffened plates, we divide the explosion load in a cabin into the initial explosive shock wave load and quasi-static air pressure load and use finite element analysis software LS-DYNA to simulate and calculate the damage characteristics of fixed stiffened plates under the explosion load. [
Methods] In this paper, the deformation characteristics of the stiffened plate under the same impulse and peak load are simulated, and the damage characteristics of the stiffened plate under the initial explosive shock wave load, quasi-static air pressure load, and the combined action of the two loads are analyzed. [
Results] The results show that when the impulse acting on the stiffened plates is equal and the load action time is less than 0.05 times the vertical first-order natural vibration period, the final deflection value of the stiffened plates is near the maximum value. When the load peaks are equal, there is a saturated impulse value, after which the loading time no longer affects the final deformation of the stiffened plates. [
Conclusions] The final deformation of stiffened plates under an explosion load in a cabin is not a simple superposition under the action of two loads; the combined effect of the two loads enhances their damage.
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Objectives] In order to develop a computation method for the bending issue of corrugated core sandwich panels and solve the bending deflection and stress of such panels, this paper proposes an equivalent stiffness method. [
Methods] First, the middle cores of these sandwich panels are taken as equivalent to orthotropic elastic materials. Then, the equivalent elastic modulus of the cores is solved by Castigliano’s theorem and the integral stiffnesses of the sandwich panels are calculated by the laminate theory. According to the solved integral stiffness constants, the distribution of bending deflection is achieved by solving the bending equilibrium equations of orthotropic panels, and stress distribution is derived by adopting Hooke’s law. [
Results] It is validated that the stiffness error evaluated by this proposed method is −6.98% in comparison with the method in Ref. [7]); the maximum error of deflection is −2.01% and stress is 3.63%, which correspond to the FEM results. [
Conclusions] This proposed method for calculating integral stiffness through layered accumulation not only avoids the complicated derivation of applying the method in Ref. [7] completely but also satisfies calculation precision when computing the bending issue.
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Objectives] The rigidity of composite marine propellers is lower than that of traditional metal rigid propellers, and the deformation of the blades under fluid-structure interaction has an obvious effect on hydrodynamic and noise performance. It is therefore particular to the composite propeller model test. [
Methods] Dimensional analysis is used to build a special similarity relation and conversion method for the hydrodynamic and noise performance of the composite propeller. To meet the requirements of the model test, the special test technology is analyzed according to the processing of the composite propeller model and its fluid-structure interaction characteristics. [
Results] The composite propeller model test, besides satisfying the similarity relation to the metal propeller model test, also essentially satisfies the similarity relation of the blade’s hydrodynamic deformation. [
Conclusions] Unlike traditional metal propellers, the composite propeller offset, mechanical properties, and dynamic deformation of the blades must be collected in the test, so as to select a reasonable model scale and propeller model material. Meanwhile, not only must the same dimensionless advance coefficient between the model and full-scale propeller be kept, but also the combined similarity of stiffness characteristics and Mach number of the blade tip must be met.
[Objectives] In order to realize the digitalization, networking, and intellectualization of ship steam power systems, this paper puts forward an application system based on a digital twin model. [Methods] The “four-dimensional thought model” of a ship steam power system based on a digital twin is proposed, covering the four dimensions of physical objects, process elements, life cycle, and virtual space. The “five-stage system model” of the whole life cycle of the power system is then built, including five typical stages: concept demonstration, system design, general assembly and construction, trial run, and operation and maintenance. Advanced technologies such as big data, the internet of things, cloud computing, artificial intelligence, and model-based system engineering are introduced, and the overall digital twin “seven-layer architecture model” of a ship steam power system is formed, composed of the physical layer, interface layer, data layer, model layer, scheduling layer, function layer, and application layer. [Results] The verification results of the virtual design analysis and test platform of the ship steam power system show that the digital twin system framework can effectively support the system’s scheme design, operation analysis, and test scheme evaluation, and realize interaction and cooperation between the physical space and virtual space throughout the whole life cycle of the ship. [Conclusions] The results of this study can provide valuable references for the overall digital design of ship steam power systems.
[Objectives] In order to explore the laws of the emergency surfacing motion of submarines, this paper used a simplified model of propeller volume force to carry out the numerical simulation of submarine emergency surfacing motion at different speeds. [Methods] Numerical simulations of the underwater fixed depth, ascent, and surfacing of the hull were carried out, and submarine buoyancy at different speeds was compared and analyzed by matching the screw rotation speed with the speed of the submarine, as well as its surfacing time and attitude. [Results] As the results show, at a faster rotation speed, the time for the submarine to gain steady speed and maintain fixed depth underwater is shorter. Regardless of the trim angle or heeling angle, the time when the angle changes for the first time and that when the peak occurs show a trend of reduction although the rotation speed increases. At the same time, with the increase in rotation speed, the fluctuation time of trim angle increases, while the fluctuation time of heeling angle decreases. [Conclusions] The relevant calculation methods and results of this study can provide practical references for research on submarine-based emergency surfacing motion.
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Objectives] To address the unstable power output of photovoltaic systems on the mobile platforms of ships and power fluctuations caused by sudden loading/unloading, this paper proposes an energy management strategy involving a photovoltaic hybrid energy storage system based on optimal power distribution. [
Methods] In view of the shortcomings of the traditional limit management method, the filter time constant is adaptively adjusted according to the different zones of the state of charge of the supercapacitor, thereby realizing the optimal power distribution of the hybrid energy storage system. Meanwhile, the control strategy and working mode of each converter are analyzed. [
Results] The Matlab simulation results and engineering test results show that the energy management scheme and converter control strategy can effectively improve the overcharge or over-discharge problem of hybrid energy storage systems, not only ensuring the stability of the DC bus voltage but also improving the dynamic response and coordination of the system. [
Conclusions] The results of this study can provide references for the energy management of photovoltaic systems on mobile platforms.
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Objectives] Aiming at the application of digital twin technology to marine power systems (MPSs), this paper investigates the technology route being adopted to implement digital twin in the design process of MPS, which exhibits features of high integration and full-life-cycle development. [
Methods] A digital twin technical system is researched in accordance with the characteristics of MPS development, making use of a set of advantages of the digital twin, such as virtual reality fusion and real-time interaction, iterative operation and optimization, and all-element all-process data drive. [
Results] The structures of digital twin top-level system framework, platform construction system, key technology system, and digital twin model construction system are constructed. [
Conclusions] The results of this study can provide quantitative support for the demonstration applications and practices of MPSs based on digital twin technical systems.
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Objectives] Aiming at improving the schematic design efficiency of ship air-conditioning ventilation system and reducing the difficulty of data management, we propose a rapid schematic generation method based on knowledge components. [
Methods] First, the design process for the schematic design of the air-conditioning ventilation system is analyzed, and the knowledge component model, entity modeling, and instantiation process are defined on this basis. Next, combined with the design characteristics of the air-conditioning ventilation system, the business model and data exchange model are designed on the basis of the knowledge components. Finally, a prototype system of schematic design is developed using AutoCAD and PDM and then verified through application in actual engineering design. [
Results] The result shows that the schematic design efficiency of the air-conditioning ventilation system is increased by 43.5%. [
Conclusions] This method can be widely used in the schematic design of the ship system. It can greatly improve the design efficiency and the capability of data management and has a certain value in practical application.
