Automakers aren’t the only ones looking to increase fuel efficiency and decrease emissions. Aircraft manufacturers are facing similar requirements, and they’re using high-tech gadgetry to help them meet those goals.
Researchers at Iowa State University are using particle image velocimetry and molecular tagging velocimetry and thermometry to study the performance of nozzles that spray fuel into jet engines. The work could spur development of more efficient nozzles that allow aircraft to run leaner fuel mixtures without sacrificing performance. That would save fuel — and money — while also reducing oxide of nitrogen emissions, improving air quality and reducing aviation’s carbon footprint.
Hui Hu, an associate professor of aerospace engineering, and his team use two tools to study the efficiency of fuel nozzles:
- Particle image velocimetry, which uses a laser and camera to take nearly simultaneous images that show the movement and velocity of individual spray droplets.
- Molecular tagging velocimetry and thermometry, which uses lasers to illuminate and tag groups of molecules and a camera to capture images that reveal the velocity, temperature and density of those molecules.
The tools help the researchers understand the uniformity, direction, temperature and density of fuel droplets sprayed by the nozzles, how they mix with air and how they behave as the temperature changes. “Engine efficiency and emissions are closely related to the quality of the fuel spray,” Hu said. “How uniform is the spray before it is burned?”
Hu is working with engineers from Goodrich Corp. Engine Components, which hopes to develop more efficient fuel nozzles. “We’re looking at these diagnostic studies and then taking that information to impact our designs and improve gas turbine engines,” said Kevin Gordon, vice president of technology.
Photo: Bob Elbert / Iowa State University. Hui Hu, left, and Zifeng Yang analyze the performance of a fuel nozzle