Imaging and measuring the atomization process in a gas turbine combustor using the bright x-rays from the U.S. Department of Energy’s Advanced Photon Source has been chosen by RDECOM Research Laboratory, the Army's corporate research laboratory under the Army Research Laboratory (ARL), as one of the 2018 top 10 “coolest” advances, showcasing what Army scientists and engineers are doing to support the soldier of the future. The RDECOM Research Laboratory’s chief scientist, Dr. Alexander Kott, handpicked these ARL initiatives.
“Number 7: Peeking inside a gas turbine's combustor with a strong X-ray” highlights studies carried out at X-ray Science Division (XSD) x-ray beamline 7-BM at the APS, an Office of Science user facility at Argonne National Laboratory.
The ARL notes that, “Previously it was impossible to image and measure the atomization process in a gas turbine combustor. Now, for the first time ever, Army scientists discovered a way to do this with an experiment at Argonne National Laboratory's Advanced Photon Source.
“ ‘We had a combustion going on, which was done for the first time ever at [the Advanced Photon Source] and we imaged the spray breakup at the very tip of the injector using an x-ray source,’ ” said Dr. Tonghun Lee, an associate professor in the Department of Mechanical Science and Engineering at the University of Illinois at Urbana-Champaign, who joined forces with the Army's corporate laboratory in 2018. “ ‘Typically that region where the liquid breaks up is very dense and it's difficult to image anything inside there.’
“Scientists said this new information will help design of future gas turbine combustors that may operate on alternative jet fuels, and to develop engines with higher power density and efficiency.”
Beamline 7-BM of the APS is dedicated to time-resolved x-ray radiography, tomography, and fluorescence spectroscopy using a high-intensity microbeam. Users of this beamline come from industry, academia, and a number of government research labs. They mainly study transient fluid flowfields (for example, high-speed liquid sprays and compressible gas flowfields). However, other types of time-resolved radiography measurements can also be accommodated. Additionally, the beamline performs hard x-ray tomography using filtered bending magnet white beam. Thanks to the high-brightness APS x-rays, users of this beamline have been able to access a wide range of heretofore inaccessible research avenues including imaging of cryogenic rocket sprays, imaging vapor distribution in beryllium alloy and aluminum alloy injector nozzles, and metered dose sprays from over-the-counter nasal inhales to name a few.
Alan Kastengren of the XSD Time Resolved Research Group and beamline 7-BM primary contact, said of the ARL studies, “These experiments represent a real milestone for our efforts at 7-BM to study complex flowfields. They are paving the way to expand our capabilities to serve the combustion and aerospace communities, from studying fundamental the science of combustion to exploring engineering for hypersonic flight.”
The “Top 10” gas turbine imaging joined a roster of research breakthroughs that included “Transporting quantum information with minimum distortions,” “Brain-like computer solves super-complex problems,” “A super-hero nanocrystalline alloy,” “Extreme power for jumping robots,” and “Taming the atom.”
The ARL has the mission to discover, innovate, and transition science and technology to ensure dominant strategic land power.
The original ARL press release, “Lab reveals top 10 coolest science, technology advances from 2018,” can be read here.