Parametric linear vibration response studies for longitudinal whole-body gradient coils: Theoretical predictions...

Area of Science:

• Mechanical Engineering
• Medical Imaging Physics

Background:

• Gradient coil (GC) cylinder vibration is a critical factor in passive vibration reduction for Magnetic Resonance Imaging (MRI) systems.
• A comprehensive understanding of how physical parameters influence vibration response is essential for effective design and noise mitigation.

Purpose of the Study:

• To investigate the impact of variations in gradient coil cylinder physical parameters on displacement response.
• To identify which parameters are most sensitive in affecting vibration and explore potential strategies for vibration reduction.

Main Methods:

• Utilized a linear elastodynamic Z-coil model to simulate vibration response.
• Analyzed the effects of independent, regularized variations in cylinder length, radial thickness, mass density, Poisson ratio, and Young's modulus (stiffness).
• Focused on whole-body GC cylinders subjected to Z-coil winding excitation.

Main Results:

• Displacement response exhibited complex behaviors across different excitation frequencies.
• Vibration response was particularly sensitive to changes in cylinder geometry (length and thickness) and mass density.
• Except for stiffness, no single parameter range effectively reduced vibration across all frequencies of interest.

Conclusions:

• Increasing cylinder stiffness above 100 GPa is predicted to reduce vibration for frequencies below 2000 Hz under typical conditions.
• Optimizing geometry and mass density are crucial for managing gradient coil vibration, but stiffness plays a unique role in broad frequency reduction.