Flash X-Ray System
Abstract
Flash X-Ray System:A two-channel flash X-ray system is requested to support research on advanced warhead development at the University of Illinois in the laboratory of Nick Glumac. The current facilities operated by Dr. Glumac conduct several hundred tests involving high explosives every year in sizes from the gram scale to the kilogram scale. Current diagnostics focus on external viewingof the tests using high speed cameras and spectrometers which analyze the light emitted by the every bright, opaque clouds of debris that obscure any activity inside the fireball. In order to understand why a particular system fails or succeeds (andthus be able to design the next generation of warhead), one must be able to resolve the action within the fireball and at short, precise intervals. Flash x-ray provides this capability by sending photon beam through the debris cloud and providing snapshot of the internal structure of the target at critical times in the explosive event. The beam lasts roughly 20 billionths of a second,effectively stopping the motion of the event. A two channel system allows two pictures to be taken very close together in time to evaluate the motion of the warhead and target components.Dr. Glumac is already engaged in research on advanced shaped charges which often have problems associated with unstable jetting, and the flash X-ray system will allow the viewing of the jet coherency within flight (as opposed to simply looking at the target afterwards), to assess the performance of a shaped charge system design. Additionally, a program at UIUC involving fragmenting reactive cases for advanced munitions will benefit in a similar way. Reactive caseperformance is thought to be strongly determined by the fragmentation size distribution generated by the explosive/case interaction. Currently, this is measured by soft-catch, which is indirect and hard to interpret. By using flash X-ray, fragmentation of a warhead and the distribution spatially of the fragments can be evaluated directly during a test, providing unique insight into the energetic event. Also, ongoing work with explosively generated plasmas will beassisted by the flash X-ray system. These plasmas are thought to have a different target damage mechanism than conventional explosives, though this concept is based primarily on ex-situ analysis. Flash x-rays allow direct imaging of plasma/target interactions at the critical times,allowing one to visualize the mechanism behind the target defeat.Proposed research with ONR includes investigation enhanced underwater blast systems, and other concepts whereby reactive metals aid the warhead performance. Underwater blast environments are especially opaque, and thus flash X-ray capability will allow Dr. Glumac to better visualizes these systems to understand how the metal is contributing to the reactivity of the warhead system.Future research in additive manufactured energetic materials and evaluation of custom explosive designs at UIUC will also be enabled by this purchase. Safety issues will be managed by the Division of Research Safety at the University of Illinois, which oversees other x-ray based facilities. The proposed systems will be easily accommodated in existing labs to operate on events in the explosive test chambers. Funding is requested for a two-channel flash x-ray system. The vendor quote for two-channel flash x-ray system is attached to this budget justification. The flash x-ray system is a single piece of capital equipment. Per the solicitation requirements and consistent with University of Illinois policy, indirect costs will not be assessed on this equipment purchase.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 20, 2020
- Source ID
- N000142012757
Entities
People
- Nick Glumac
Organizations
- Office of Naval Research
- United States Navy
- University of Illinois Urbana–Champaign