Multiple shaped charge jet (SCJ) warhead

Abstract

In a MSCJ warhead detonation of the main charge is controlled to provide elevated pressure at multiple locations on the back surface of the liner to cut the liner and to form and propel forward a plurality of SCJs. An initiation system is configured for multi-point initiation of a plurality of booster charges to detonate the main charge to produce a plurality of detonation waves that constructively interfere at multiple locations on the back surface of the liner to form pressure hot spots that cut the liner and to form and propel forward a plurality of SCJs. In different embodiments, the elevated pressures are between 110% and 200% of the detonation pressure at the front of an individual detonation wave. The liner may, for example, include a plurality of recesses such as shallow dimples or deeper conical structures in which case the boosters are aligned to the center of the recessed structures.

Claims

1. A warhead having a height H1 along an axis and a diameter D1, comprising: a main charge; a liner on a top surface of the main charge; a plurality of booster charges spaced apart on a bottom surface of the main charge; and an initiation system configured for multi-point initiation of the plurality of booster charges to detonate the main charge to produce a plurality of detonation waves; wherein the liner is positioned within a defined range from the plurality of booster charges equal to a height H2 of the main charge along the axis in which 0.3<=H1/D1<=0.6 such that pairs of directly adjacent detonation waves constructively interfere to form elevated pressures at multiple locations on the back surface of the liner to cut the liner and to form and propel forward a plurality of shaped charge jets (SCJs).

2. The warhead of claim 1, wherein the elevated pressures at the multiple locations is at least 110% a detonation pressure at the front of the detonation waves between the locations.

3. The warhead of claim 2, wherein the elevated pressures at the multiple locations is up to 200% of the detonation pressure.

4. The warhead of claim 1, wherein the liner includes a plurality of recesses, wherein the plurality of booster charges are aligned to the centers of the recesses such that each recess is cut and formed into a SCJ.

5. The warhead of claim 1, wherein each SCJ has a tip velocity of 4-10 km/s and a penetration depth of 7-10 a diameter of the corresponding recess.

6. The warhead of claim 4, wherein each recess has an apex angle of less than 180.

7. The warhead of claim 4, wherein each recess is a dimple having an apex angle of 120-170.

8. The warhead of claim 4, wherein each recess is a conical structure having an apex angle 40-120.

9. The warhead of claim 4, wherein each recess has a recess diameter D2 across the axis, wherein 0.5<=H2/D2<=1.5.

10. The warhead of claim 1, wherein the initiation system comprises: an inert housing including a single point initiation site and a plurality of tracks that connect the single point initiation site to the plurality of booster charges; explosive material in the plurality of tracks; and a detonator at the single point initiation site, wherein initiation of the detonator produces detonation waves that travel through the explosive material in the tracks to initiate the plurality of booster charges.

11. The warhead of claim 10, wherein the plurality of tracks are equal length to facilitate simultaneous initiation of the plurality of booster charges.

12. A warhead having a height H1 along an axis and a diameter D1, said warhead comprising: a main charge having a height H2; a liner on a top surface of the main charge, said liner having a plurality of recesses each having a diameter D2 and an apex angle less than 180; a plurality of booster charges spaced apart on a bottom surface of the main charge and aligned to centers of the plurality of recesses; and an initiation system configured for multi-point initiation of the plurality of booster charges to detonate the main charge produce a plurality of detonation waves; wherein the liner is position within a defined range H2 from the plurality of booster charges in which 0.3<=H1/D1<=0.6 and 0.5<=H2/D2<=1.5 such that pairs of directly adjacent detonation waves constructively interfere to form elevated pressures at multiple locations on the back surface of the liner at the edges of the recesses to cut the liner and to form the recesses into a plurality of shaped charge jets (SCJs) that are propelled forward.

13. The warhead of claim 12, wherein the elevated pressures at the multiple locations between 110% and 200% of a detonation pressure at the front of the detonation waves between the multiple locations.

14. The warhead of claim 12, wherein each recess is a dimple having an apex angle of 120-170 or a conical structure having an apex angle of at most 40-120.

15. A warhead having a height H1 along an axis and a diameter D1, comprising: a main charge; a liner on a top surface of the main charge, said liner having a plurality of recesses; a plurality of booster charges spaced apart on a bottom surface of the main charge and aligned to centers of the plurality of recesses; and an initiation system including an inert housing having a single point initiation site and a plurality of tracks that connect the single point initiation site to the plurality of booster charges, explosive material in the plurality of tracks and a detonator at the single point initiation site, wherein initiation of the detonator produces detonation waves that travel through the explosive material in the tracks to initiate the plurality of booster charges to detonate the main charge and produce a plurality of detonation waves; wherein the liner is positioned at a defined range from the plurality of booster charges equal to a height H2 of the main charge along the axis in which 0.3<=H1/D1<=0.6 such that pairs of directly adjacent detonation waves constructively interfere to form elevated pressures at multiple locations on the back surface of the liner at a pressure between 110% and 200% of a detonation pressure of a single detonation wave to cut the liner and to form and propel forward a plurality of shaped charge jets (SCJs).

16. The warhead of claim 14, wherein each recess is a dimple having an apex angle of 120-170 or a conical structure having an apex angle of at most 40-120.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1A-1C are different views of an embodiment of a multiple SCJ warhead;

(2) FIGS. 2A and 2B are views of different embodiments of a liner having a pattern of dimples and a liner having a pattern of conical structures, respectively;

(3) FIGS. 3A-3B are different views of an embodiment of a multi-point initiation system for the multiple SCJ warhead; and

(4) FIGS. 4A-4J are a time-series of plots illustrating a detonation sequence to form and propel multiple SCJs from a single warhead.

DETAILED DESCRIPTION

(5) The present disclosure provides a multiple SCJ (MSCJ) warhead in which detonation of the main charge is controlled to provide elevated pressure at multiple locations on the back surface of the liner to cut the liner and to form and propel forward a plurality of SCJs.

(6) Referring now to FIGS. 1A-1C, an embodiment of a multiple SCJ warhead 100 includes a cylindrical housing 102 that contains a main charge 104, a liner 106 on a top surface of the main charge, a plurality of booster charges 108 in a booster housing 110 and spaced apart on a bottom surface of the main charge, and an initiation system 112. In this embodiment, liner 106 includes a plurality of recesses 114 in the surface of the liner. Each recess 114 has an apex angle that is less than 180 e.g., each recess exhibits a curvature, it is not flat. The amount of curvature and the thickness and contoured thickness of the recess can be controlled to form the individual SCJ. Booster charges 108 are aligned to the center of the recesses 114. Initiation system 112 is configured for multi-point initiation of the plurality of booster charges 108 to detonate the main charge 104 to produce a plurality of detonation waves that constructively interfere at multiple locations on the back surface of the liner to cut the liner and to form and propel forward a plurality of SCJs. The elevated pressures at the multiple locations are between 110% and 200% of the detonation pressure at the front of an individual detonation wave.

(7) Pairs of directly adjacent detonation waves produce the multiple locations in a non-planar wave within a defined distance range from the plurality of booster charges. The liner is positioned within that range. Short of that range adjacent detonation waves do not interfere sufficiently to form the elevated pressure location and beyond that range interference of the plurality of detonation waves forms a planar wave. Within this range, the warhead (liner, main charge, boosters and initiation system) has a height H1 along the axis and a diameter D1 across the axis, wherein 0.3<=H1/D1<=0.6. By comparison, typical single SCJs form a planar wave have a ratio >1. Each SCJ has a tip velocity of 4-10 km/s and a penetration depth of 7-10 the diameter of the corresponding recess. The main charge has a height H2 along the axis and a recess diameter D2 across the axis, wherein 0.5<=H2/D2<=1.5.

(8) The plurality of booster charges may be indirectly detonated from a single point detonator or directly detonated by a plurality of individual detonators. The booster charges may be detonated simultaneously or in a timing pattern to control the formation of individual SCJs and the pattern of SCJs.

(9) Referring now to FIG. 2A, in one embodiment the recess is a dimple 200 e.g., a depression or indentation in the surface of the liner. The apex angle 202 is suitably 120-170 about an axis 204 of the warhead and more typically 150-170. Each dimple has uniform thickness in this embodiment. For example, each dimple 200 may have a radius of 1 inch and a thickness of 0.090 inches.

(10) Referring now to FIG. 2B, in one embodiment the recess is a conical structure 210. The apex angle 212 is suitably 40-120 about an axis 214 of the warhead and more typically 40-80. Each conical structure may have uniform thickness or may be thinner at the center and thicker at the edges to better form the SCJ.

(11) By comparison, single SCJ warheads that use a planar wave to form the liner into a SCJ typically have conical structures with an apex angle of approximately 60. Structures with apex angles greater than 60 will not properly form into the metal jet.

(12) The elevated pressures not only cut the liner but form each recess into a metal jet. Because the pressure levels on the edge of each recess are at least 110% of the front of the detonation wave, much shallower recesses can be formed into a SCJ. This increases the design space for the recesses in the liner and the formation of the SCJs.

(13) Referring now to FIGS. 3A-3B, in an embodiment, an initiation system 300 includes an inert housing 302 having a single point initiation site 304 and a plurality of tracks 306 that connect the single point initiation site to the plurality of booster charge sites 308. Explosive material 310 is placed in the plurality of tracks. A detonator 312 at the single point initiation site produces detonation waves that travel through the explosive material 310 in the tracks to the booster charge sites 308 initiate the plurality of booster charges. The plurality of tracks may be equal length to facilitate simultaneous initiation of the plurality of booster charges or different lengths to facilitate a patterned initiation of the plurality of booster charges.

(14) Referring now to FIGS. 4A-4J, in an embodiment, the plurality of boosters 108 are simultaneously initiated by the initiation system to initiate booster waves 400 that continue forward within the booster charge sites 308 within the inert housing 110. Booster waves 400 transfer detonation to main charge 104 to form detonation waves 402 that propagate forward through main charge 104. As each detonation waves 402 constructively interferes with the directly adjacent detonation wave 402, hot spots 404 of elevated pressure are defined at multiple locations that are approximately aligned to the edges of dimples 114. As previously described, the hot spots 404 form within a distance range from the boosters. If the liner is too close to the boosters 108 that hot spots 404 will have not yet formed. If the liner is too far away, the plurality of detonation waves 402 will interfere and level off into a single planar wave. The front of each detonation wave 402 impacts the bottom of each dimple and then the hot spots 404 reach the liner at the edges of the dimples 114 and cut into the liner 106 to form multiple SCJs 406, one for each dimple 114. The detonation waves 402 independently accelerate and form each SCJ 406, which are propelled forward.

(15) In comparison to existing single SCJs that produce a planar detonation wave to form the SCJ, the current design requires a main charge with less height H2, hence less volume to form the elevated pressure hot spots. Furthermore, formation of the hot spots to cut the individual dimples or conical structures produces SCJs that are better and more uniformly formed than a single planar detonation wave. Lastly, the current design produces multiple SCJs in a single warhead.

(16) While several illustrative embodiments of the disclosure have been shown and described, numerous variations and alternate embodiments will occur to those skilled in the art. Such variations and alternate embodiments are contemplated, and can be made without departing from the spirit and scope of the disclosure as defined in the appended claims.