62results about How to "Reduced Radiation Efficiency" patented technology

The present invention provides an acoustic material structure and assembly method of an acoustic material structure and an acoustic radiation structure. The acoustic material structure includes acoustic units and openings; the acoustic units are attached to the surface of the acoustic radiation structure; the acoustic unit comprises a sheet; cavities are defined between the sheets and the acousticradiation structure; the openings pass through the acoustic units respectively; one end of the opening is communicated with the corresponding cavity; the opening can reduce the spring effect of a medium in the cavity, so that the acoustic unit enables a low frequency sound insulation effect even if being attached onto the surface of the acoustic radiation structure; the acoustic unit may also comprises a supporting body, a mass block and a constraining body; the operating frequency of the acoustic unit can be adjusted through the supporting body, the mass block and the constraining body; theacoustic material structure can well suppress the sound energy radiation of large wavelengths in middle and low frequency bands with low weight and low space cost ensured; and the vibration of the sheets can be utilized to enhance the exchange rate of the medium attached to the surface of the acoustic radiation structure, and therefore, through-flow heat dissipation performance can be improved.