New temperature sensor sounds good

New temperature sensor sounds good
Acoustic thermometers could be used in hostile industrial environments (image courtesy of iStockphoto)

Temperature scientists at NPL are developing a thermometer that uses sound waves to measure temperature.

The thermometer works on the principle that the speed of sound changes with , travelling faster through warmer air. Such an instrument could potentially replace traditional thermometers in environments where cause a loss of accuracy.

NPL's Michael de Podesta, who leads Acoustic Thermometry research, said, in an interview with The Engineer magazine: "Potential uses include any hostile environment [for example] inside a furnace above 1,000 °C."

"Any contact thermometer used in this environment degrades as soon as it is used and is usually placed in the environment inside a protective tube. The practical acoustic thermometer consists just of the tube itself."

The acoustic works by transmitting along a gas-filled tube from a speaker at one end to a microphone at the other. By measuring the amount of time it takes the sound waves to travel along the tube, the temperature can be calculated.

"The principle is very simple but the application is pretty complicated," said Dr Rob Simpson from the Engineering Measurement team. "The difficult part is working out how to produce the sound and then how to listen to it."

Acoustic thermometry offers a cheap and robust alternative to current instruments, and could potentially reduce the need for equipment to be replaced and calibrated, providing cost and efficiency savings to industry.


Explore further

Scientists design bomb-proof thermometer to measure the heat of explosions

Provided by National Physical Laboratory
Citation: New temperature sensor sounds good (2011, June 2) retrieved 28 February 2021 from https://phys.org/news/2011-06-temperature-sensor-good.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
0 shares

Feedback to editors

User comments