Determination of detonation front curvature radius of ANFO explosives and its importance in numerical modelling of detonation with the Wood-Kirkwood model

Scientific paper - Original scientific paper

• Title (croatian): Određivanje polumjera zakrivljenosti fronte detonacijskoga vala ANFO eksploziva i njegova važnost u numeričkome modeliranju detonacije primjenom Wood-Kirkwoodova modela
• Author: Barbara Štimac Tumara
• Author: Mario Dobrilović
• Author: Vinko Škrlec
• Author: Muhamed Sućeska
• Author's institution: University of Zagreb; Faculty of Mining, Geology and Petroleum Engineering; (Department of Mining and Geotechnical Engineering)
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mining, Petroleum and Geology Engineering

Abstract (english)

Unlike most military high explosives, which are characterized by an almost plane detonation front, ammonium nitratebased commercial explosives, such as ANFO (ammonium nitrate/fuel oil mixture) and emulsion explosives, are characterized by a curved detonation front. The curvature is directly related to the rate of radial expansion of detonation products in the detonation driving zone and the rate of chemical reactions, and it is one of the characteristics of nonideal explosives. The detonation theories used to model the nonideal behaviour of explosives require both reaction rate and rate of radial expansion to be known/specified as input data. Unfortunately, neither can be measured and what is mostly used is a link between these rates and parameters which can be more easily measured. In this paper, the Wood-Kirkwood approach of determination of radial expansion through the radius of detonation front curvature and the electro-optical technique for experimental determination of detonation front curvature of ANFO explosives is applied. It was shown that an experimentally determined radius of detonation front curvature vs charge diameter, incorporated in the Wood-Kirkwood detonation theory, can satisfactorily reproduce experimental detonation velocity-charge diameter data for ANFO explosives, especially when the pressure-based reaction rate law is also calibrated (D=1.3 and k=0.06 1/(μs/GPaD)).

Abstract (croatian)

Za razliku od većine vojnih visokih eksploziva, koje karakterizira gotovo ravna fronta detonacijskoga vala, komercijalne eksplozive na bazi amonijeva nitrata, kao što su ANFO i emulzijski eksplozivi, karakterizira zakrivljena fronta detonacijskoga vala. Zakrivljenost je izravno povezana s brzinom kemijskih reakcija i brzinom radijalnoga širenja produkata detonacije u zoni pokretanja detonacije i jedna je od karakteristika neidealnih eksploziva. Teorije detonacije, koje se koriste za modeliranje neidealnoga ponašanja eksploziva, zahtijevaju da se kao ulazni podatci znaju/specificiraju i brzina reakcije i brzina radijalnoga širenja. Nažalost, ni jedno ni drugo ne može se izmjeriti, pa se najčešće koristi veza između tih brzina i parametara koji se mogu lakše mjeriti. U radu smo primijenili Wood-Kirkwoodov pristup određivanja radijalnoga širenja preko polumjera zakrivljenosti fronte detonacijskoga vala te mogućnost eksperimentalnoga određivanja zakrivljenosti fronte detonacije ANFO eksploziva elektrooptičkom metodom. Pokazalo se da tako određen polumjer zakrivljenosti fronte detonacijskoga vs promjera naboja, ugrađen u Wood-Kirkwoodovu teoriju detonacije, može na zadovoljavajući način reproducirati eksperimentalne podatke o brzini detonacije i promjeru naboja ANFO eksploziva, pogotovo sa zadovoljavajućom kalibracijom modela brzine reakcija ovisne o tlaku (D = 1,3 i k = 0,06 1/(μs/GPaD)).

• Keywords (english): ANFO; nonideal detonation; detonation front curvature radius; detonation velocity; numerical modelling
• Keywords (croatian): polumjer zakrivljenosti; brzina detonacije; ANFO; neidealna detonacija; numeričko modeliranje
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Rudarsko-geološko-naftni zbornik
• Numbering: vol. 37, no. 2, pp. 97-107
• p-ISSN: 0353-4529
• e-ISSN: 1849-0409
• DOI: https://doi.org/10.17794/rgn2022.2.9
• URN:NBN: urn:nbn:hr:169:998562
• Publication: 2022
• Project: Number: IP-2019-04-1618; Title (croatian): Poboljšani model neidealne detonacije gospodarskih eksploziva; Title (english): An improved model of non-ideal detonation of commercial explosives; Acronym: NEIDEMO; Leader: Muhamed Sućeska; Jurisdiction: Croatia; Funding stream: IP
• Document URL: https://hrcak.srce.hr/273880
• Type of resource: Text
• Access conditions: Open access
• Created on: 2024-01-25 13:54:01