针对某燃油箱在振动耐久性试验中油箱共振引起下箱体的振幅过大和底部破裂的问题,对该油箱进行扫频激振试验分析,发现有半箱水时会降低油箱的阻尼振动频率。利用有限元软件Hypermesh对该油箱模型进行模态分析得到该油箱的固有频率并与扫频激振试验结果对比。提出了三种下箱体底部结构的设计方案来改变该油箱的固有频率,并对结构改进后的油箱进行扫频激振试验。结果表明,改进后的油箱的固有频率有所提高。 Aiming at the problem of tank amplitude and bottom rupture caused by tank resonance in the vibration durability test of a certain fuel tank, the tank was subjected to swept-frequency excitation test and analysis. It was found that the damping vibration frequency of the tank was decreased when there was a half tank of water. Using the finite element software Hypermesh, the natural frequency of the fuel tank model was obtained by modal analysis and compared with the result of sweeping vibration test. Three design schemes of the bottom structure of the lower tank are proposed to change the natural frequency of the tank and the swept-frequency vibration test of the oil tank with the improved structure is carried out. The results show that the improved natural gas tank has increased.