Date Available
6-16-2025
Year of Publication
2025
Document Type
Master's Thesis
Degree Name
Master of Science in Aerospace Engineering (MSAeroE)
College
Engineering
Department/School/Program
Mechanical Engineering
Faculty
Dr. Michael Renfro
Abstract
In pursuit of measuring different variables present in bourbon barrels, absorption spectroscopy was utilized to ensure that different ethanol and water concentrations can be differentiated using a broadband light source and near infrared spectrometer in a simple cuvette-based testing setup. The intensity and absorption plots gathered of different ethanol and water mixtures were then analyzed using proper orthogonal decomposition (POD) to break down the data into modes which represent specific variables of interest, specifically ethanol concentration or alcohol by volume (ABV). The modes were then utilized to find mode constants to represent the data taken from cuvette samples which were then plotted to find trendlines which can be solved to find ABV given the mode constant of a sample. With this method the sampling method was expanded to measure depth using handmade borosilicate glass probes. The probes were designed to fit through a bourbon barrel bung and feature a smooth curve at the bottom of the probe, a bumpy section comprised of glass beads and two leads to attach fiber optic cables to. The bumpy section utilizes high light loss across the glass beads and different indexes of refraction between the liquid and air to measure depth. POD analysis is then done on intensity data taken from the glass probes in a calibration set of different depth and ethanol concentrations observed in a lab setting. ABV and depth values were able to be determined when the other variable was known but not while both were unknown. More comprehensive analysis methods are in development as part of future work. In tandem to solving the closure problem, probes were placed in situ in barrels at a barrel warehouse where measurements were taken successfully for multiple months.
Digital Object Identifier (DOI)
https://doi.org/10.13023/etd.2025.253
Funding Information
This study was supported by grants from Jim Beam Brands from 2022-2024.
Recommended Citation
Reed, Trent T., "In Situ Bourbon Barrel Measurements of Alcohol by Volume and Liquid Depth Using Borosilicate Glass Probes and Near Infrared Absorption Spectroscopy" (2025). Theses and Dissertations--Mechanical Engineering. 239.
https://uknowledge.uky.edu/me_etds/239
