Numerical simulation on frequency shift of thin plate with lumped mass block

The theoretical analysis and frequency calculation of a thin plate with additional mass blocks were performed to achieve the main parameters of mass blocks that affect the dynamic characteristics of the thin plate. The influence of mass block parameters such as mass value, position, quantity, media, and distribution area on the frequency of the thin plate was discussed with the finite element method. The numerical simulation results show that, when the structural frequency shift is realized by adding mass blocks, it is necessary to lay the lumped mass blocks whose mass value is less than 10% of the total structure mass at the wave peak of the structural mode shape so that the greatest shift of frequency can be achieved. For the thin plate immersed in heavyweight fluid, much greater additional mass should be added to obtain the required shift of frequency. Moreover, for the high-rank mode shape, mass blocks should be symmetrically laid at the wave peak of the structural mode shape. The further application study on frequency shift of thin plates on the basis of this study may be useful for altering natural frequency and reducing vibration in the modification of thin plate structure.