THERMAL SCIENCE

International Scientific Journal

Yuxin Ye

,

Peizhe Zou

,

Chao Han

,

Xiaoyu LiangORCID

STUDY ON TEMPERATURE MEASUREMENT AND EXPERIMENT OF LOOSE COAL BASED ON ACOUSTIC THERMOMETRY

ABSTRACT
In order to enhance the accuracy of temperature measurement for loose coal using acoustic methods, this study constructed an experimental system based on the principle of acoustic thermometry. The system was designed to investigate the influence mechanisms of acoustic signal frequency, sensor spacing and temperature on the acoustic wave propagation characteristics. The acoustic wave transit time was measured under different frequency ranges, sensor spacings, and temperature conditions during the experiments. The results show that the acoustic transit time tends to stabilize in the range of 400-1000 Hz and 2000-3000 Hz, and the acoustic wave propagation effect is superior, which is more suitable for the preferred frequency range of the acoustic wave transit time test. The acoustic wave transit time increases with the sensor spacing, and the growth rate of the acoustic transit time in different frequency ranges shows a significant difference. As temperature rises, the acoustic wave transit time shows a decreasing trend, and the relative error between the inverted temperature and the reference temperature based on the acoustic temperature measurement model is 2.27%-7.13%, which verifies the reliability and accuracy of the model. This study provides important theoretical foundations and experimental basis for the accurate measurement of spontaneous combustion temperature in loose coal.
KEYWORDS
Acoustic temperature measurement, Loose coal, coal spontaneous combustion, Acoustic wave transit time
PAPER SUBMITTED: 2025-04-29
PAPER REVISED: 2025-07-26
PAPER ACCEPTED: 2025-09-05
PUBLISHED ONLINE: 2025-11-08
DOI REFERENCE: https://doi.org/10.2298/TSCI250429184Y
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2026, VOLUME 30, ISSUE No. 2, PAGES [1535 - 1545]
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Study on temperature measurement and experiment of loose coal based on acoustic thermometry

© 2026 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence