Modal analysis through response-based FRFs: Additional modes for local diagnoses

In order to ensure the safety and stability of the oil tank in the transportation process, the dynamic response of the tank body was simulated, tested and optimized based on the finite element method and vibration testing technology. The modal vibration modes were calculated respectively under the conditions of 50 %, 75 % and 100 % liquid filling of the oil tank, and the influence of the oil content on the overall structure mode was obtained. Under the full load condition, the stress response under continuous and non-continuous impact loads was calculated. Based on the analysis results, the vibration damping elements were arranged, and the optimization effect of vibration reduction was verified and analyzed by vibration testing. The results show that full load is more conducive to the stability of the oil tank, and the vibration damping element can reduce the maximum amplitude by more than 80 %, which has good economic and social benefits.

Section: Introductionmentioning

confidence: 99%

Modal analysis and vibration response test of tank body

Kong,

Cheng

2024

“…In order to ensure the smooth operation of the anchor components, a large support structure needs to be installed. The operating speed of the anchor machine rotor system is not constant, and the resonance problem generated by the rotor must be considered [2,3]. Pre-stress modal analysis of the support structure must be carried out to obtain the natural frequency and corresponding vibration mode, which can be used as a reference for the operating frequency of the rotor to prevent structural damage caused by resonance and ensure safe operation.…”

Section: Introductionmentioning

confidence: 99%

Analysis and optimization of pre-stressed modal features of ship anchor support parts

Liu,

Wu,

Calderon

2024

In order to solve the problems of excessive weight and unreasonable structure of anchor machine parts caused by traditional design methods, a lightweight optimization method was proposed based on pre-stressed modal analysis. The design variables were determined, and the parameterized model was established by using ANSYS Workbench. Under ultimate load conditions, the strength of wall frame board and lower box bodies was simulated and calculated. Through modal analysis, the discretized natural frequencies under different design variables could be obtained. The multi-objective genetic algorithm and sequence quadratic programming were respectively used to calculate the lightweight analysis model. The results showed that the weight of the supporting components in ship anchor can be reduced by more than 5 % without reducing strength and equivalent stiffness.

“…Composite pipelines, as an engineering structure for transporting gases and liquids, are widely used in fields such as nuclear industry, aerospace, and shipbuilding [1][2][3]. During the service process of a composite pipeline structure, the instability of the fluid motion state can cause displacement and deformation of the pipeline, which in turn affects the fluid state [4,5]. This interaction between the fluid and the structure is called fluid solid coupling [6].…”

Section: Introductionmentioning

confidence: 99%

Analysis of vibration response characteristics of composite pipeline based on finite element method

2024

In order to ensure the good stability of the composite pipeline under fluid dynamic loads, finite element analysis method was applied to simulate and calculate the modal characteristics under dry and wet mode conditions. According to the working principle and structural characteristics of composite pipelines, the model was parameterized and simplified to improve computational efficiency and convergence. The modal testing platform is constructed, consisting of a combination of pipeline structure and pipeline support structure. The movement direction of the slider is limited by the guide rail used, allowing the horizontal section of the branch to move only along its own pipeline axis direction. The fluid structure coupling analysis technology was applied to obtain the vibration mode and spectral response results of the composite pipeline, which was verified through an experimental platform. The research results indicate that the natural frequency in wet mode was about 16 % lower than that in dry mode. In addition, it could be proven that the simulation scheme had good computational accuracy, with a maximum error of 9.2 %.