In this paper,the research object of helicopter composite sound absorption is single degree of freedom noise reduction honeycomb sandwich structure.This paper conduct theoretical research on noise absorption and parameter design of micro perforated plate aperture,perforation rate,etc.according to noise characteristic of helicopter cabin,and complete the manufacturing of composite sound absorbing structure test pieces through some key technology research.A good effect has been verified on the hot break adhesive film of micro perforated plate and honeycomb,with hole breaking rate of 100%.Two schemes were used for bonding the test piece,with a through-hole rate of over 98%,meeting the requirements.The plane tensile strength of bonding scheme 1 was higher,making it more suitable for manufacturing composite sound ab-sorbing structure components.The vertical incident sound absorption coefficient of this structure is above 0.5 in the frequen-cy range of 1600-3600 Hz,which indicating that this structure has a good sound absorption effect on the main reducer and engine compartment sound field of helicopter.The research results can be beneficial for helicopter vibration and noise reduc-tion in the future.
helicopternoise of cabinnoise reduction honeycombs sandwich structuremicro-perforated plate
万方数据
维普
