摘要
基于半解析半数值法研究了水中环肋锥柱结合壳在低频范围内的结构振动特性。将环肋锥柱结合壳离散为锥壳分段、柱壳分段、圆环板和舱壁等不同子结构。用波传播法和幂级数法分别求解圆柱壳和圆锥壳的运动方程。通过相邻子结构之间的连续条件以及壳体两端的边界条件求解锥柱结合壳的振动响应。在锥壳或柱壳上施加点力激励,分析锥柱结合壳的频响特性。用有限元方法验证本文的计算结果,两者吻合良好。还研究了舱壁、环肋和流体负载对环肋锥柱结合壳振动特性的影响。
A semi-analytical and semi-numerical method is developed for the vibration analysis of a submerged cone-cylinder combined shell at low frequencies. The coupled shell is divided into different kind of substructures: cylindrical shells, conical shells, annular circular plates and bulkheads. The cylindrical shell and the conical shell equations of motion are solved through wave approach and power series respectively. Boundary conditions and continuity conditions are used to form final matrix and calculate dynamic response of the coupled shell. Under different excitations set at cone or cylinder, vibration characteristics of the coupled shell are discussed. Numerical results are in good agreement with analytical ones. Effects of bulkheads, ring stiffeners and fluid on the coupled shell are discussed.
引文
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