无人航行器水密舱段振动特性理论分析模型研究

Research on Theoretical Models of Vibration Characteristics of Unmanned Underwater Vehicle Watertight Compartments

摘要:

无人航行器水密舱段作为全平台的主要结构，建立其准确的结构振动特性预报模型，明晰外界环境因素变化影响规律，对实现整体方案及详细设计等阶段的快速迭代具有重要意义。针对这一问题，将水密舱段合理简化为有限长含内部环肋圆柱壳结构，以能量变分原理为基础，分别对壳体结构能量、环肋结构能量、外流场耦合能量（可计及自由液面影响）、静水压力预应力能量等依次进行理论推导；明确上述能量项具体表达形式后，得到壳–液耦合振动能量泛函，对能量泛函变分后成功建立壳体振动特性计算分析模型。通过与公开文献以及有限元软件计算结果进行对比，计算模型的准确性得到了充分验证。随后，利用该模型， 对潜深等因素所引起的圆柱壳振动特性变化进行了深入分析讨论，阐明有关现象背后的数学物理机理。

Abstract:

The watertight compartment is the main structural component of unmanned underwater vehicle platform. Establishing an accurate structural vibration prediction model of the watertight compartment and clarifying the influence of changes in external environmental factors are of great significance for rapid technological iteration in the overall design and detailed design stages. To address this issue，the watertight compartment is reasonably simplified as a finite-length cylindrical shell structure with internal ring stiffeners. Based on the principle of energy variation，theoretical derivations are carried out for the energy of the shell structure，the energy of the ring stiffeners， the fluid coupling energy（including the influence of the free surface），and the pre-stress energy due to hydrostatic pressure. After clarifying the specific expressions of the above energy terms，the vibration energy functional of the shell-liquid coupling is obtained. By varying the energy functional，a calculation and analysis model for the vibration characteristics of the shell is ultimately established. The accuracy of the calculation model in this paper is fully verified by comparing it with published literature and finite element software results. Subsequently，using this model，an in-depth analysis and discussion of the changes in the vibration characteristics of the cylindrical shell caused by factors such as dive depth are conducted，elucidating the mathematical and physical mechanisms behind the phenomena.