Simplified and Extended Gurney Formulas for Imploding Cylinders and Spheres

Ein vereinfachtes Modell fur die Voraussage von Hohlladungs-Parametern Das Modell basiert auf fruheren Arbeiten von Hirsch und den ursprunglich analytischen Arbeiten von Pugh, Eichelberger und Rostoker. Dabei wird die von Hirsch abgeleitete vereinfachte Gurney-Gleichung fur implodierende Zylinder mit der PER-Theorie kombiniert unter Bildung eines eindimensionalen Computer-Codes und dam angewendet zur Voraussage der,Parameter eines Hohlladungsstachels mit 80 mm Durchmesser. Gute Ubereinstimmung mit den experimentellen Daten wurde erreicht. Un modele simplifie en vue de prevoir les parametres des charges ereuses Le mod6le est fond6 sur d'anciens travaux de Hirsch et les travaux analytiques initiaux de Pugh, Eichelberger et Rostoker. Pour ce faire, on combine 1'6quation de Gurney dtrivCe et simplifiCe par Hirsch pour cylindres implosants 2 la thCorie PER en formant un code informatique unidimensionnel, puis on l'utilise pour prhoir les paramttres d'un jet de charge creuse de 80 mm de diamttre. On a obtenu une bonne concordance avec les donn6es exp6rimentales. Summary Description of the ModelThe model is based on the more recent work of Hirsch and the original analytical work of Pugh, Eichelberger and Rostoker. Namely, the simplified Gurney formula for imploding cylinders derived by Hirsch is combined with the PER theory forming one-dimensional computer code, and then it is used for predicting the 80-mm diameter shaped charge jet parameters. Good agreement has been found with the experimental results.

Section: Introductionmentioning

confidence: 99%

The Simplified Model for Predicting Shaped Charge Jet Parameters

Gui‐Xi¹

1995

“…The work proposed by Gurney in 1943 [13] stands as fundamental when referring to velocities of fragments from explosively-driven metal casings [14][15][16][17].…”

Section: Theoretical Approachmentioning

confidence: 99%

Numerical Simulation and Experimental Tests on Explosively‐Induced Water Jet Phenomena

Enache

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et al. 2016

This study addresses some aspects regarding water jet propulsion during high explosives detonation. A number of theoretical and experimental studies have shown that using Gurney equation and the relationships derived, one can provide fair results regarding initial velocity of metallic fragments for explosively‐driven metal casings. However, an investigation on Gurney equations utilization for the prediction of water velocity has not been performed yet. By carrying out simple experimental tests and numerical simulations, water has been investigated in terms of total mass average velocity and tip velocity. Based on the available data, the findings indicate that Gurney equations overestimate the water mass average velocity. For water tip velocity evaluation, further studies should be made.

On the inconsistency of the asymmetric‐sandwich gurney formula when used to model thin plate propulsion

Hirsch¹

1995

The asymmetric sandwich Gurney formula is used extensively worldwide during explosive reactive armor and shaped‐charge war‐head design, in either its original form(1,2) or its extended form used to model implosion configurations(3–5). It is therefore very important to realize that calculations may contradict physical observations when the formula is used to calculate the velocity of thin plates having mass which is smaller than half the explosive mass per unit area. This inconsistency between calculation and experimental results is explained as resulting from the failure of the assumption made in deriving all the Gurney formulas that the velocity distribution of the explosive products is a linear function of the expansion coordinate.