Voxelgrids Innovations, founded in 2017 by Dr. Arjun Arunachalam, has developed India’s first locally manufactured commercial 1.5 Tesla (T) MRI scanner, with the machine already deployed at Chandrapur Cancer Hospital in Chandrapur, Maharashtra.
The key challenge in MRI development lies in the conventional reliance on large volumes of liquid helium to cool superconducting magnets — a process that is both expensive and can take several weeks. Voxelgrids aimed to address this by developing a conduction-based cooling system using a mechanically coupled cryocooler (cold head), which extracts heat directly from the magnet through conduction, eliminating the need for liquid helium entirely.
To validate and refine this cooling design without repeated physical prototyping, the team used COMSOL Multiphysics® software with its Heat Transfer Module. The model incorporated thermal contact resistance at mechanical joints, radiative heat exchange inside the vacuum chamber, and complex two-stage cooling behaviour — creating a virtual replica closely resembling real-world conditions.
Key outcomes of the simulation-led approach include:
- Virtual cooldown analysis completed in a matter of hours, enabling evaluation of multiple cold head configurations, interface materials, and mechanical layouts
- Detailed temperature contours and gradient plots helped identify areas of trapped heat and poor thermal pathways, guiding mechanical design iterations
- Critical failure modes safely simulated, including accidental overlap of first and second stage temperatures, confirming thermal isolation under real-world conditions
- Simulation predictions closely matched experimental cooldown results, with observed differences attributed to factors not included in the initial model
- Significant reduction in overall product development time, compressing months of trial-and-error into days of virtual experimentation
The resulting MRI scanner is compact, lightweight, and aims to make MRI diagnostics accessible and affordable in settings with challenging installation conditions across India.
Image courtesy: COMSOL Inc.
