Dynamic behaviors of flexible fluid containers with fuel consumption

This study focuses on the dynamic characteristics of the containers with fuel consumption. With fuel consumption, the fuel container system vibrates with decreasing mass, which is a typical variable mass system. In order to investigate the influences of the time-varying liquid on vibration of the containers, this fluid-structure coupling system with time-varying mass is modeled combining finite element method, used to model the structure, and virtual mass method representing the fluid. The dynamic responses and time-frequency analysis of the time-varying mass system are presented based on the numerical simulations. From the results, it is shown that decrease of the mass results in increase of the vibration frequencies of the system and induces an additional negative damping. The additional negative damping is proportional to the rate of mass change and causes the vibration to decay slowly. The results also suggest that the time-frequency analysis possess appealing advantages in processing nonstationary signals and thus are able to provide reliable time-frequency domain information for time-varying mass systems.