Device records blast temperatures
Device records blast temperatures
2008-10-02Newsfeed
A thermometer has been developed that is hardy enough to record the changing temperatures produced in an explosion.
A thermometer has been developed that is hardy enough to record the changing temperatures produced in an explosion.
Scientists from the UK's National Physical Laboratory set off a series of controlled detonations in order to test the strengths and effectiveness of different designs.
Lead researcher Dr Gavin Sutton told the New Scientist: "The hostile environment and the complex physics and chemistry of the explosion process are very challenging.
"An explosion generates a shock wave, significant amounts of heat, and particulate matter such as soot, all of which could degrade or damage a thermometer."
Dr Sutton said devices such as thermocouples, which measure the voltage produced by differing temperatures in a metal, react to slowly and are damaged by the process. Laser can also be used but are too expensive and difficult to use.
The team eventually decided on an optical fibre surrounded by sand in a steal tube. The device measures thermal electromagnetic radiation produced from the explosion and converts it into current. The thermometer can produce a detailed profile of temperature changes during an explosion by taking 50,000 measurements per second.
"The lab tests of our portable thermometer regularly measured fireball temperatures of 3,000 kelvin and above without any damage," Dr Sutton said.
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