Sound insulation effect of magnetorheological fluid as a function of magnetic field strength and direction

IMPACT STATEMENT Sound transmission loss was significantly increased by sound insulation effect of a magnetorheological fluid as a function of magnetic field strength and direction. We developed a sound absorber using a magnetorheological fluid(MR-F) based on the density and alignment angle of carbonyl iron powder(CIP) chains by the controlling the magnetic field strength and direction. The magnetically arranged CIP lattice structure considerably influenced the sound transmission loss(STL). We used optical microscopy, energy-dispersive X-ray spectrometry, and X-ray diffraction to investigate the STL by varying the magnetic field strength from 0 to 40 mT and the angle from 0 to 30 degrees. The STL was markedly increased (133%) owing to an similar to 10-fold increased density and the CIP alignment. These results were verified using the developed MR-F porous model.

Automated summary

This study developed a sound absorber using a magnetorheological fluid (MR-F) and investigated the effect of magnetic field strength and direction on sound transmission loss (STL). The results showed that by controlling the magnetic field conditions, the STL could be significantly increased, mainly due to the changes in density and alignment angle of the carbonyl iron powder (CIP).