第1个回答 2011-05-30
Ship is a maritime military, transportation and entertainment in one of the major carriers, both in the industrial age or in the rapid development of logistics industry in the 21st century, plays an important role. The important factors affect the safety of the ship structure and equipment is one of the vibration and noise, not as technology development, are increasingly the subject on the agenda, a modern cutting-edge research topics. Currently, the hull structure of the modal analysis, impact analysis of shell structure has been gradually carried out, and made some effective solution, but the core structure of the ship cabin and the coupling between the vibration analysis equipment, there are still many gaps. Analysis of the bottom layer of pure structure or equipment, can not truly reflect the actual structure of the vibration, structural response caused by many factors, such as the connection mode, support layout, structural stiffness, functioning and so on.
Based on the current situation, this article summarizes the structure of the vibration of the ship, the engine vibration analysis, finite element method of connection handling, structural stiffness of the vibration, etc., in turn, leads to a double bottom ship host and cutting-edge coupled vibration analysis of subjects . Integrated to improve accuracy and reduce the computational requirements of the scale, and different ways of connection, through the finite element software ANSYS, the establishment of the ship master and double bottom coupling structure model for the future analysis of the vibration characteristics of the foundation and structural optimization
First, the finite element model modal analysis and constraint free modal analysis, the natural frequency changes with the joint stiffness in the different rules should be noted that bolt preload can not just change the connection and processing of joint surface; followed the host load calculation, simplification and load, the coupling of the double bottom structure of the host and multiple transient dynamic analysis, the results showed that treatment of three-dimensional springs and coupling all degrees of freedom coupled vibration analysis method in almost the same; and Analysis lateral support to the supported host layout, and give two methods of support to the structural vibration response analysis of vibration response when the bilateral support to small; the final calculation of static analysis using four kinds of structural stiffness of the double bottom, to be transient analysis compare the results obtained greater structural rigidity, the smaller the vibration response, the more stable, meaning that the smaller the vibrational energy is passed, but the quality and shape are different, according to the ship on the vibration and noise, quality, speed, etc. different requirements for the design of ship structure, ship building, vibration control and the safety of navigation provided a good theoretical basis.
第2个回答 2011-06-08
Firstly established finite element model to free modal analysis and the constraints that modal analysis, system inherent frequency with the change rule of connecting stiffness different, need to be aware that can't literally change bolt pre-tightening force and processing connection with face; Second through the host load calculation, simplify and loading, to host and double bottom coupling structure transient dynamic analysis of multiple, the results showed that the 3d spring processing method and the method of freedom in the coupling all coupling vibration analysis of nearly identical; Then analysis to the lateral braces host decorate way, and support gives two kinds of strut way of structural vibration response analysis, bilateral support to small; when vibration response Finally using statics analysis and calculation of the double bottom four structure stiffness, be transient analysis, comparison results obtained, the greater the vibration response structure stiffness, the more stable the smaller, i.e. the smaller vibration energy, but quality and form different, so according to the ship for vibration noise, quality, ship speed and so on the different requirements for design, hull structure for shipbuilding, vibration control and navigation safety provides a good theory.