Vibro-acoustic Analysis And Control Of Metal-nonmetal Materials Structure

With the development of materials design and manufacture level, composite materials are used in field of army marine as their low-density, high-stiffness and high-damping. Composite zxes, composite mounting and composite screw are used step by step in the foreign countries and get favorable vibration and noise control effect. The exploration of composite structure is begun and some products are made. As a whole, dynamic design theory and calculation prediction method of metal-nonmetal integrated structure is lag. The vibration control method study of metal-nonmetal integrated structure has important application value.In this paper, the FE-SEA hybrid method of all-domain dynamic mechanics integrative analysis of marine mounting is studied by VA One software. Large complex structure model building for al-domain vibration and noise analysis in one computing workplace is realized. Vibration and noise calculation in low, middle and high frequency domain is finished for the foundation of vibration and noise control effect evaluation of metal-nonmetal materials integrated structure.Connection stiffness and damping of the metal-nonmetal bracket structure are the important factor of vibration mechanics characteristics. Without changing bracket structure's shape, size, simulation load mass and finite increment of bracket structure mass, the finite element numerical calculation is used to analysis the vibration control effect of bracket structure in condition of setting vibration inspirit, select and evaluate several setting project by changing joint damping of bracket structure, restrict damping of bracket structure beam, filling rubber damping in joint. Vibration level difference is the widely used damping effect evaluation method for the convenient measurement. This method has the problem of no capability to describe system vibration energy. Power flow level difference, a new evaluation method, can describe vibration energy distributing and attenuation discipline in the system but have its difficult measurement. In this paper, the finite element power flow equations of beam and plate integrated structure are given. Virtue and defect of two evaluation methods are discussed by calculating the element power flow level difference and the vibration level difference of beam and plate combination structure. Study shows, integrated structure optimization design model based on restrict of vibration level difference and power flow level difference can get optimization design result according with engineering fact. In this paper, the metal-nonmetal materials structural optimization model in condition of vibration level difference and power flow level difference restricted can acquire optimization design is given and solved by multi-island heredity method. Numerical optimization results prove excellent vibration control capability of metal-nonmetal materials integrated structure.