Combustible metallic igniter casing for tank guns

39 Pages·1.195 MB·English

by  Robbins F.W., Bundy M.L., Von Wahlde R.

AD-A243
269
MEMORANDUM REPORT BRL-MR-3944
BRL
COMBUSTIBLE METALLIC IGNITER
CASING FOR TANK GUNS
C LEE-T-T(F lf F. W. ROBBINS
DE0 111991 M. L. BUNDY
U
R. VON WAHLDE
NOVEMBER 1991
APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED.
U.S. ARMY LABORATORY COMMAND
BALLISTIC RESEARCH LABORATORY
ABERDEEN PROVING GROUND, MARYLAND
91 1'209 058
NOTICES
Destroy this report when it is no longer needed. DO NOT return it to the originator.
Additional copies of this report may be obtained from the National Technical Information Service,
U.S. Department of Commerce, 5285 Port Royal Road, Springfield, VA 22161.
The findings of this report are not to be construed as an official Department of the Army position,
unless so designated by other authorized documents.
The use of trade names or manufacturers' names in this report does not constitute indorsement
of any commercial product.
UNCLASSIFIED ]
Form__________
REPORT DOCUMENT PAGE
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1. AGENCY USE ONLY (Leave blank) REPORT DATE 3.* TYEA DEDOART ES COVERED
IFinal
INovember 1991 Jan 90 - Jan 91
4. TITLE AND SUBTITLE S. FUNDING NUMBERS
Combustible Metallic Igniter Casing for Tank Guns PR: 1L161 102AH-43
6. AUTHOR(S)
F.W. Robbins, M.L. Bundy and R. Von Wahilde
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) S. PERFORMING ORGANIZATION
REPORT NUMBER
9. SPONSORINOIMONITORING AGENCY NAMES(S) AND ADDRESS(ES) 10.SPONSORING/MOINITORING
AGENCY REPORT NUMBER
USA Ballistic Research Laboratory
ATT7N: SLCBR-DD-T
BLM 34
Aberdeen Proving Ground, MD 21005-5066BR- -94
11. SUPPLEMENTARY NOTES
128. DISTRIBUTION/AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE
Approved for Public Release - Distribution is Unlimited
13. ABSTRACT (Maxkmm 200 wods)
Calculations have shown that a combustible metallic igniter casing for tank cannon can be made to withstand the
pressure loads created by combustion of the igniter charge, yet - when consumed by the flame of the main
charge - not adversely elevate the maximum chamber pressure at any position. In particular, a finite-element
model, 1-DEAS, was used to evaluate the structural response of various combustible igniter casings when
subjected to internal pressure loads imposed by the combustion of the igniter charge. A state-of-the-art interior
ballistics code, XNOVAKTC, was used to evaluate the effect which combustion of the interior casing itself has
on maximum chamber pressures and projectile launch velocity. Initial tests have been reasonably successful.
both in demonstrating the feasibility of the concept and in yielding results not unlike those predicted from the
models.
14. SUBJECT TERMS 16. NUMBER OF PAGES
Guns, Interior Ballistics, Igniter, Structural Response, Metallic, Combustible 28
16. PRICE CODE
17. SECURITY CLAUIFICATION 18. SECUITY CLASSIFICATION 19. SECUliTY CLASSIMIATIO14 20 LIWIATION OF ASSTRACT
OF WOWT OF THS PAK OF AUSTIRACT
UNCLASSIFIED UNCLASSIFIED UNCLASSIFIED S.AR
NSN 7540-01-280-6500 UNCLASSI FIED Staid Form 298 IRev J? eq)
F,e,.rbed "' ANSI Std 139 18
298 !02
INTENTIONLY LEFr BLANK.
Acknowledgement
The authors are indebted to: Mr. Carl Ruth and the Range 18 crew of the Inte-
rior Ballistic Division of BRL for conducting the firing tests; to Donald McClellan
and Emily Hsi, BRL contractors working in the Launch and Flight Division, for
graphical support; to Larry Sturla of the Experimental Fabrication Division for
machining the test metallic igniter tubes.
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Table of Contents
Page
Acknowledgements .. .. .. ... ... ... ... ... ... ... ... .... iii
List of Figures. .. .. .. .. ... ... ... ... ... ... ... ... ... vii
List of Tables .. .. .. .. ... .... ... ... ... ... ... ... .... ix
1. Introduction .. .. .. .. ... ... ... ... ... ... ... ... ... ... 1
II. Finite-Element Modeling (FEM). .. .. .. .. ... ... ... ... ... ... 2
III. Interior Ballistics Modeling. .. .. .. .. ... ... ... ... ... ... ... 5
IV. Experimental Observations. .. .. .. .. ... ... ... ... ... ... ... 6
V. Igniter Casing Durability .. .. .. .. ... ... ... ... ... ... ..... 9
VI. Unresolved Questions .. .. .. .. ... ... ... ... ... ... ... .... 11
VII. Conclusions. .. .. .. ... ... ... ... ... ... ... .... ... .. 13
References .. .. .. .. ... ... ... ... ... ... ... ... .... .. 15
Distribution List .. .. .. ... ... ... ... ... .... ... ... .... 16
INTeNTONALLY LEfl BLANK.
List of Figures
Figure Page
1 a) Schematic of Generic Tank Gun Cartridge Case; b) FEM Grid (Using Thin
Shell Elements) for Igniter Tube ............................... 3
a) Local FEM Grid Around Igniter Vent Hole, b) 'egion of Maximum Stress
(Due to Igniter Charge Combustion) in Thin Aluminum Casing (Located
Around Inner Surface of Vent Hole), c) Deformation (Mag.=20x) Caused by
Stress Level in Fig. 2b ....... .............................. 4
3 Schematic of Igniter Tube Cross-Section with V-Groove Pattern ......... 7
4 Post-Fired 120-mm DM13 Casings, Consisting of Stub Base With Protruding:
a) Steel (Standard), b) Thick-Walled Aluminum, c) Thin-Walled Aluminum
and d) Magnesium Igniter Tubes ....... ........................ 7
5 Pressure Versus Time at Various Gauge Locations for a) Steel (Baseline),
b) Thick-Walled Aluminum, c) Thin-Walled Aluminum and d) Magnesium
Igniter Casing (Note, Zero Time Does Not Correspond to Close of the Firing
Key) .......... ........................................ 8
6 Pressure Difference Versus Time for a) Steel (Baseline), b) Thick-Walled Alu-
minum, c) Thin-Walled Aluminum and d) Magnesium Igniter Casings (Note,
Zero Time Does Not Correspond to Close of the Firing Key) ............ 10
7 Flexible Igniter-to-Primer Joint Design .......................... 12
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