Two-colour glowing molecule could make wind tunnel tests more accurate
Chemists have designed a new molecule that can emit different colours for pressure and temperature, providing a built-in way to correct a long-standing error in the specialist paints used for testing aircraft.
- Researchers have developed a single molecule capable of measuring both air pressure and temperature at the same time, overcoming a longstanding challenge in sensor technology.
- By emitting two different light signals, one affected by both pressure and temperature and another affected only by temperature, the molecule can automatically correct for temperature effects and provide more accurate pressure readings.
- Designed for use in specialist sensor paints, the breakthrough could help engineers capture more reliable pressure measurements from aircraft models in wind tunnels, even when temperatures fluctuate.
Most sensors can only measure one thing at a time: like a thermometer for temperature, or a pressure gauge for pressure. Measuring two properties accurately from the same surface, at the same moment, usually means using two separate instruments 鈥� adding cost and complexity to the process.
Measuring air pressure and temperature simultaneously
Now, chemists and aerospace engineers at 糖心Vlog官方, working with colleagues at the University of Eastern Finland, have designed a molecule that can help us to do both simultaneously. It emits two distinct colours of light at once: one that responds to both air pressure and temperature, and one that only responds to temperature. By comparing these two signals it鈥檚 possible to take a corrected pressure reading from the molecule itself, rather than having to use a separate temperature sensor alongside a pressure sensor.
The molecule has been designed to be an active ingredient in the specialist paints that measure pressure on aircraft models in wind tunnels, solving a major challenge in the aerospace industry. When engineers test a new aircraft design in a wind tunnel, they need to know exactly how air pressure is distributed across every surface. One of the best ways of doing this is by using a pressure-sensitive paint that glows in proportion to the air pressure pushing against it. The problem is that the light these paints currently emit is sensitive not only to pressure, but also to temperature. As a scale model heats and cools during a wind tunnel test, the glowing shifts in ways that have nothing to do with pressure, introducing errors that engineers then have to correct.
Our new Manchester material emits red light, what we call phosphorescence, which is sensitive to changes in both pressure and temperature. At the very same time, this material emits blue light as a fluorescence 鈥� responding only to temperature. By measuring blue and red light at once, we鈥檝e got everything we need to separate the pressure signal from the temperature interference. That kind of built-in self-correction is simply not possible with a standard light-emitting molecule.
Improving pressure-sensitive paint for aerospace applications
The team鈥檚 work, published in the journal , explains how the molecule is built around a gold atom bonded to a ring-shaped compound called acridine. The position of that bond within the structure determines which type of light the molecule produces. Gold was chosen because even subtle changes to where it sits within the molecule produce reliably different light-emitting behaviours, giving chemists precise control over the sensing properties. When the gold atom bonds to one position on the molecule, it triggers the pressure-sensitive red emission, whereas a bond at a different position triggers the temperature-only blue emission.
Calculations carried out by their colleagues in Finland, helped the team to understand and predict these differences before the molecule was built in the laboratory. Then in use, the molecule is embedded in a paint applied to test models in the standard way. A camera captures both emission colours simultaneously, and the ratio between the two signals automatically corrects for temperature, without any separate temperature sensor.
, Reader in the Department of Mechanical and Aerospace Engineering at 糖心Vlog官方, said: 鈥淚n wind tunnel testing, temperature correction is currently one of the main challenges to making pressure-sensitive paints reliable. Having both pressure and temperature measurements come from the same molecule simultaneously is a more elegant solution, and potentially a more practical one for real test conditions, where adding extra instruments creates its own complications.鈥�
The team鈥檚 work sits within a broader programme of research at Manchester into improving pressure-sensitive paint for aerospace applications. A related study, recently published in , addresses the temperature problem from a different direction, by designing a platinum-based paint with inherently low temperature sensitivity. Together, the two studies represent complementary approaches to one of the industry鈥檚 most persistent challenges.
This research has been published in: Advanced Optical Materials.
Full title of the paper: Temperature Correction in a Single Luminophore Pressure-Sensitive Paint Using a Dual-Emitting Gold Acridine Complex
DOI: 10.1002/adom.71493
URL: