2026-09-21T19:54:08Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/124425 2024-09-16 col_2142_5131 col_2142_14787 com_2142_5130 com_2142_9630 com_2142_234

Glumac, Nick G 2024-05 application/pdf en text Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2024-09-16 without embargo terms The student, Samuel Brunkow, accepted the attached license on 2024-04-27 at 18:32. The student, Samuel Brunkow, submitted this Thesis for approval on 2024-04-27 at 18:33. This Thesis was approved for publication on 2024-05-01 at 16:08. DSpace SAF Submission Ingestion Package generated from Vireo submission #20677 on 2024-09-16 at 00:37:19 Brunkow, Samuel Neal 2024-05-01 Fireball Pyrometry Spectroscopy Imaging High Explosive Secondary Explosive Structure Secondary high explosives including Composition A-5, PBXN-5, TNT, Composition B, PETN, and one metalized explosive, RDX-AL, were tested to characterize detonation fireball physical and thermal structures. Hemispherical 25-gram charges were detonated on a transparent PMMA sheet enabling optical measurements with a basal view of the fireball’s internal structure. Temperature profiles were determined through pyrometry and blackbody fitting of binned imaging spectra. The 3-color pyrometry was employed at three radial distances from the detonation center with sub microsecond temporal resolution utilizing optical fiber installed flush with the transparent sheet for light capture at 700, 900, and 1300 nm. Imaging spectra, captured at a flame front radius of approximately 3 to 4.5 inches, facilitated measurement of the thermal distribution across the flame front. Additionally, an HFSC Pro framing camera was utilized to capture the fireball directly on and as viewed from underneath. The high-speed imaging facilitated spatial characterization of the internal fireball structure at 4 diameters and qualitative assessments of hydrodynamic instabilities and relative turbulent mixing. Measurements and observations are compared with current literature and state-of-the-art theoretical models. Text eng https://hdl.handle.net/2142/124425 Copyright 2024 Samuel Brunkow Thermal and physical structures of high explosive fireballs through optical thermometry and high-speed imaging M.S. Thesis Mechanical Engineering University of Illinois at Urbana-Champaign Mechanical Sci & Engineering