Session: Medical Devices and Pharmaceuticals

Paper Number: 151136

151136 - Using 3d Measurements From Mri to Improve Vvuq 

Abstract: 

Magnetic resonance velocimetry is a measurement diagnostic that can measure 3D, three-component turbulent velocity fields in arbitrarily complex flow configurations. The approach uses magnetic resonance imaging (MRI), which is essentially a medical imaging system commonly available in radiology departments or medical research centers.  The MRI however is used in engineering applications rather than clinical or medical ones, with a primary focus on velocity measurements of hydrogen protons in water channel flows.  Within the context of these MRI studies, it is possible to additively manufacture geometrically scaled replicas of complex flow configurations that contain flow paths of diverse interests and measure water flow without optical accessibility, which is conducive to design, assessment, and understanding of critical phenomenon. Despite the obvious utility of the measurements for investigating a wide variety of flows, comparisons with computational fluid dynamic simulations largely retain traditional metrics, comparing velocity profiles and planes at discrete regions within the flow rather than using the fully 3D nature of the measured field. The data can be obtained in periods of several hours and with submillimeter measurement resolution, yielding millions of measurements with excellent applications for expanding verification and validation activities to incorporate more multidimensional techniques. In this effort, magnetic resonance velocimetry was conducted in a simple water channel with six spanwise-centered periodic obstacles roughly shaped as cubes. At a fully turbulent Reynolds number of 15,000, the channel includes two flows: a main streamwise flow and, in the wake of the second obstacle, an injected flow oriented perpendicular to the streamwise flow. The flow geometry includes partial obstacles on the side walls and is inherently 3D because of the interaction of the two streams and the wake features, making the flow challenging to completely measure with traditional optical techniques. Aside from line profiles and planar comparisons, two 3D metrics are used to compare the magnetic resonance velocimetry data with a steady Reynolds-averaged Navier–Stokes simulation result. The first metric leverages the volume of an isosurface of the velocity magnitude at a specific value, whereas the second computes the vorticity from the experimental data. An isosurface of the magnitude of this derived quantity is directly compared with the Reynolds-averaged Navier–Stokes simulation. A brief discussion about the comparison is provided, including comments about uncertainty of the data and the boundaries of the isosurfaces. The geometry used for this work is proposed for detailed additional study beyond this project, as three dimensional data sets for validation activities becomes readily available through the technique.

Presenting Author: Michael Benson Oak Ridge National Laboratory

Presenting Author Biography: COL (Retired) Michael Benson has a Bachelor of Science degree from the U.S. Military Academy at West Point, as well as Masters, Engineer, and Doctorate Degrees from Stanford University, all in Mechanical Engineering. After teaching and leading Mechanical Engineering at West Point for many years, he joined the Collection Science and Engineering Group at Oak Ridge National Laboratory in June 2023. Mike's research interests include developing and using novel diagnostics for quantitative measurements of velocity, concentration, and temperature fields in technical flows using Magnetic Resonance Imaging systems, and he is a Fellow of the American Society of Mechanical Engineering.

Authors:

Michael Benson Oak Ridge National Laboratory
Duy Thien Nguyen Oak Ridge National Laboratory
Daniel Borup Borup Solutions LLC