According to the mechanism and spectrum characteristics of an oil-free air compressor noise source, determined the muffler installed at the air inlet. According to the characteristics of noise source, muffler is designed into type of expansion chamber, considering the structural dynamic parameters, by means of optimization method to determine the size, and the finite element modal analysis is conducted. By solving the muffler's inherent frequency and mode of vibration, knows weather each order natural frequency is away from the peak frequency, the structural dynamics of the muffler can be modification. Methods of structure modal analysis and dynamic optimization on the muffler provided reliable reference to design a high efficient new muffler.

This paper takes the under-frame of 300t storage silo produced by a certain company as the main research subject,static behavior of the under-frame is analyzed by three-dimension finite element method to generalize the rule of static deformation and stress distribution.Eigenvalues can be obtained by stability analysis and global stability and the whole structure is checked.All of the above provide a reliable reference for the design of storage silo.