UNB Physics Department Seminar - FR

Event date(s): November 28, 2023
Time(s): 01:15 PM - 02:15 PM
Category: Fredericton
Location: Fredericton

UNB Physics Department Seminar
 
When: Thursday, Nov. 28 @ 1:15 p.m.
Location: Science Library, Room 107

Speaker: Sebastian Richard

Title: A Modular, Low-Field Magnetic Resonance Design with Pre-Polarization for Characterizing Flows

Abstract: Magnetic resonance (MR) has an established track record of accurately characterizing a wide range of flows non-invasively. Despite this, there has been no widespread adoption of MR flow measurements beyond the realm of MR research. This is primarily due to hardware constraints and complexity of measurement. Most existing MR based methods employ large and costly high-field superconducting magnets and switched magnetic field gradient systems. Although the use of such hardware can result in high-quality, spatially-resolved flow measurements with excellent sensitivity, its high cost and lack of portability preclude its use in practical applications outside of a research lab setting.

Over the past few years, we’ve developed and demonstrated a novel MR method that uses a series of simple MR spin-echo (CPMG) experiments to simultaneously measure both the average velocity and flow behaviour index in various pipe flows. This approach enables us to determine the flow velocity profile. This methodology is suitable for use with portable and cost-effective low-field hardware. In this talk, I will review and give updates on a new, modular, low-field design that I have developed specifically for use with our methodology.  The design is based on low-cost ceramic magnets. It consists of a sensor built using a pitched magnet arrangement in combination with several modular pre-polarizing units to facilitate a controlled pre-polarization length for measurements on flows that require a significant amount of time in a magnetic field to become polarized (e.g., aqueous solutions).  This design addresses many of the practical limitations that have prevented widespread adoption of MR-based flow measurements. Future improvements to address current limitations will also be discussed. 

Building: Science Library

Room Number: 107