Validation and Calibration of a Millimeter Wave Interferometer for Concentration Measurements in Particle-Laden Flows

32 Pages Posted: 15 Nov 2024

See all articles by Nicolas Rasmont

Nicolas Rasmont

University of Illinois at Urbana-Champaign

Joshua Rovey

University of Illinois at Urbana-Champaign

Laura Villafane

University of Illinois at Urbana-Champaign

Abstract

Millimeter-wave interferometry is a novel method for measuring absolute concentrations in opaque dispersed multiphase flows. Its advantages include: the ability to penetrate dense particles clouds with minimal transmission loss compared to optical radiation (i.e., near-visible light), a linear response to volume fraction that is mostly independent of particle properties, the use of safe non-ionizing radiation, kilohertz sampling rates, and compact low-cost hardware. Spatial resolution is the main limiting factor of the technique when sub-centimeter resolution is required. In this work, we compare two methods to calibrate a millimeter wave radar interferometer for absolute concentration measurements: a direct method that uses known particle concentrations, and an indirect method that relies on measuring the relative permittivity of bulk particle samples. Direct calibration results derived from earlier work by the authors are improved through the use of high-resolution X-ray micro-tomography to measure the particle size distribution and overlap-tolerant particle counting algorithms. The indirect calibration method utilizes a custom interference-based technique to measure the relative permittivity of a bulk powder at millimeter wave frequencies. Results from both calibration methods agree within 0.7 % when using the Lichtenecker logarithmic effective medium equation.

Keywords: Millimeter-wave interferometry, Multiphase flow diagnostics, Concentration measurements, Dielectric permittivity measurement, Optically opaque particle-laden flows, Non-intrusive diagnostics.

Suggested Citation

Rasmont, Nicolas and Rovey, Joshua and Villafane, Laura, Validation and Calibration of a Millimeter Wave Interferometer for Concentration Measurements in Particle-Laden Flows. Available at SSRN: https://ssrn.com/abstract=5022662 or http://dx.doi.org/10.2139/ssrn.5022662

Nicolas Rasmont (Contact Author)

University of Illinois at Urbana-Champaign ( email )

601 E John St
Champaign, IL 61820
United States

Joshua Rovey

University of Illinois at Urbana-Champaign ( email )

601 E John St
Champaign, IL 61820
United States

Laura Villafane

University of Illinois at Urbana-Champaign ( email )

601 E John St
Champaign, IL 61820
United States

Do you have a job opening that you would like to promote on SSRN?

Paper statistics

Downloads
35
Abstract Views
133
PlumX Metrics