Analysis of dynamic response characteristics of vehicle-mounted tank based on the finite element method

The vehicle-mounted tanks face prominent challenges in balancing dynamic safety, including vibration resistance and fatigue durability under complex transportation conditions. A rigid-flexible coupled finite element model, consisting of the base, tank body, and frame, was established. Vibration response analysis was conducted in accordance with ride comfort standards and road excitation requirements. Rigid-flexible coupled simulations were implemented with consideration of vertical acceleration inputs and road unevenness. For random vibration, power spectral density analysis demonstrated that the tank structure was prone to resonance in specific frequency bands. For structural optimization, key dimensions were selected as design variables, including vertical thickness, longitudinal thickness, middle width, and lateral width. An optimization mathematical model was established, and the Sequential Quadratic Programming (SQP) algorithm was adopted to solve the constrained nonlinear multi-objective optimization model. Through optimization calculations, the structure achieved 4.93 % reduction in mass, 37.3 % decrease in stress, and 37.1 % increase in the first-order natural frequency, thereby effectively balancing the requirements of lightweight design, structural strength safety, and anti-resonance performance. This study provided a comprehensive methodology for the dynamic analysis and optimization of vehicle-mounted tank containers, offered key technical support for advancing innovative studies in transportation and vibration engineering.