Analysis of an MRI Gradient Coil Duct with a Micro-perforated Panel Acoustic Absorber

作者：Li Gemin^*; Mechefske Chris K

来源：Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering , 2010, 37B(3): 103-115.

DOI：10.1002/cmr.b.20162

• MRI acoustic noise
• gradient coil
• finite cylindrical duct
• Boundary Element Method
• micro-perforated panel
• acoustic absorber

An analytical model was developed for an MRI gradient coil duct with a micro-perforated panel (MPP) acoustic absorber placed inside the duct. The absorption coefficients of a series of MPP absorbers with varying design parameters including diameter of the holes, perforation rate and thickness of the air gap were calculated. Boundary Element Method (BEM) models were then developed for the coil duct with MPP absorbers and porous materials with varying design parameters and material properties. The acoustic power, sound pressure levels and sound field inside the duct were calculated using the BEM. The results show that the principal advantage of an MPP acoustic absorber is its effectiveness in absorbing relatively low frequency noise. By using the proper combination of parameters, a MPP acoustic absorber can be designed to be a wide band absorber or a narrow band absorber at any specific central frequency.

• 出版日期2010-8