Quantifying Argon Concentration within Insulating Glass Units using Low Frequency Ultrasonic Technique

TL;DR

This paper introduces a nondestructive ultrasonic method to accurately measure Argon gas concentration in insulating glass units, enhancing energy efficiency assessments and maintenance of building insulation.

Contribution

The study develops and validates a novel ultrasonic technique for quantifying Argon in IGUs, outperforming existing methods in accuracy and providing a practical tool for building insulation monitoring.

Findings

Ultrasonic energy increases with higher Argon concentration.

The method achieves a mean absolute error of 0.13 in measurements.

Outperforms Spark Emission Spectroscopy and ISO-GAS-Control in accuracy.

Abstract

Insulating glass units (IGUs) account for over 30% of thermal transmission losses in building envelopes. To mitigate this, IGUs are often filled with low-conductivity gases like Argon. However, Argon concentration decreases over time due to IGU aging and manufacturing processes, which lessens their insulating effectiveness. This study presents a novel nondestructive methodology to quantify Argon concentration in IGUs using ultrasonic technique. The ultrasonic energy transmitted through the IGU is correlated with Argon concentration, validated through both experimental measurements and numerical models using COMSOL Multiphysics. The models simulate acoustic-structure interaction by adjusting gas density to reflect Argon presence, showing increased ultrasonic energy with higher Argon concentrations. Experimental measurements on two IGU samples with twenty Argon-air mixtures (ranging from 100% to 25% Argon) show that the proposed ultrasonic technique achieves a mean absolute error of 0.13, outperforming Spark Emission Spectroscopy and Helantec ISO-GAS-Control, which have errors of 2.31 and 0.33, respectively.