Method for reducing violence of accidental explosions in solid fuel rocket motors and other energetic devices

Abstract

A method and system for reducing the violence of an accidental explosive reaction of an energetic material, the method comprising: (a) obtaining a solid energetic material configured for use within an energetic device, the energetic material comprising at least one void formed therein; and (b) filling at least a portion of the at least one void with an inert, incompressible material configured to mechanically stabilize the energetic material to prevent the void from collapsing and the surface area of the energetic material from increasing in the event of an insult tending to damage the energetic the material. In one exemplary embodiment, the inert, incompressible material is configured to temporarily modify the energetic device, meaning that the inert, incompressible material is configured to be removably inserted or otherwise applied to the energetic device.

Description

RELATED APPLICATIONS [0001] This application claims priority to U.S. Provisional Application Ser. No. 60 / 579,938, filed Jun. 14, 2004 and entitled, “Method of Reducing Vulnerability and Violence of Explosive Response to Solid Rocket Motors,” which is incorporated by reference in its entirety herein.FIELD OF THE INVENTION [0002] The present invention relates to explosives and various energetic devices, such as solid fuel rocket motors, comprising an energetic material or explosive medium. More particularly, the present invention relates to various methods and systems for reducing the violence or intensity of accidental explosion of all or a portion of the energetic material or explosive medium within such energetic devices, which accidental explosion is triggered by an insult of one or more types, such as a thermal or mechanical insult, that occurs while handling, storing, or transporting the energetic device, or during other activities involving the energetic device. BACKGROUND OF T...

AI Technical Summary

Benefits of technology

[0018] In light of the problems and deficiencies inherent in prior related energetic devices, the present invention seeks to overcome these by rendering energetic devices, and more particularly the energetic material contained within the device, less susceptible to responses currently identified as violent. Stated differently, the present invention seeks to overcome the above-described deficiencies by reducing the relative violence or intensity resulting from an insult-induced or accidental explosion of an energetic device. In doing so, it may be possible to classify suitably equipped energetic devices under a less restrictive categorical division, which would effectively reduce the costs associated with the manufacture, transportation, storage, and deployment of the energetic device, and more importantly, the hazards associated with accidental explosions, such as danger to personnel and equipment.

[0019] In accordance with the invention as embodied and broadly described herein, the present invention features a method for reducing the violence of an accidental explosive reaction of an energetic material, the method comprising: (a) obtaining a solid energetic material configured for use within an energetic device, the energetic material comprising at least one void formed therein; and (b) supplying, filling, or otherwise applying at least a portion of the at least one void with an inert, substantially incompressible material configured to mechanically stabilize the energetic material to prevent the void from collapsing and the surface area of the energetic material from increasing in the event of an insult tending to damage the energetic the material. It is preferred that the inert, incompressible material conform to the void or other geometric configuration.

[0021] The present invention further features a method for facilitating a reduction in violence of an accidental explosive reaction of an energetic material, the method comprising: (a) providing an inert, substantially incompressible material configured and intended for insertion into a void of an energetic material, the inert, incompressible material being configured to mechanically stabilize the energetic material to prevent the void from collapsing and the surface area of the energetic material from increasing in the event of an insult tending to damage the energetic material; and (b) facilitating the application of the inert, incompressible material to the energetic material.

[0022] The present invention still further features an energetic material configured for use within an energetic device, the energetic material comprising: (a) a substantially solid body configuration having at least one void formed therein; and (b) an inert, substantially incompressible material removably disposed within at least a portion of the void, the inert, incompressible material being configured to mechanically stabilize the energetic material to prevent the void from collapsing and the surface area of the energetic material from increasing in the event of an insult tending to damage the energetic the material, the inert, incompressible material reducing the violence of an accidental explosive reaction of the energetic material.

Problems solved by technology

However, these structures or voids tend to make the energetic material susceptible to collapse upon localized internal pressurization, thus potentially creating additional burning surfaces that can increase the violence, or rather the intensity, of an explosion.

Division 1.1 explosives comprise a mass explosion hazard.

Division 1.4 explosives present a minor explosion hazard.

Therefore, from a manufacturer's standpoint, the lower the division in which an explosive device may be categorized, the higher the costs and more restrictive the imposed requirements will be for handling and storing that particular explosive device.

In addition, the lower the division, the greater danger there is to equipment and personnel in the event of an accidental explosion.

During even carefully deliberative handling and storage of energetic or explosive devices, there still remains a risk of accident that may result in hazardous ignition of the explosive material contained within the energetic device.

Indeed, the energetic device may be inadvertently subjected to one or more types of insults, such as mechanical or thermal insults.

Both mechanical and thermal insults typically function to mechanically or structurally damage the energetic material, which effectively increases the surface area of the energetic material, thus potentially increasing the reaction violence or reaction intensity in the event of an accidental or inadvertent ignition, resulting in an explosion involving the energetic material.

One common type of thermal insult is accidental fire, such as that caused by spilled and ignited fuel.

Being somewhat unintuitive, it has been discovered that an insult induced explosion is relatively less violent when the energetic material is subjected to a rapid rate of external heat flux, such as when the energetic device is engulfed in flames.

A rapid rate of heat flux causes a relatively less violent explosion because of the non-uniform heating of the energetic material as a whole.

Conversely, an insult induced explosion is relatively more violent when the energetic material is subjected to a slow rate of external heat flux, such as when the energetic device is exposed for a prolonged period of time to a thermal source (e.g., when the energetic device is partially engulfed in flames or adjacent to or in close proximity to flames).

A slow rate of heat flux produces a more violent explosion because the energetic material, as a whole, is more uniformly heated.

Because all of the energetic material ignites simultaneously, more explosive power, and therefore more energy, is released, thus resulting in an explosion that is much more violent.

However, this is often not possible.

As can be seen from the above discussion, any mechanical or thermal insult resulting in damage to the energetic material will result in a much more violent explosion than normal due to the fact that the effect of the insult is to increase the explosive surface area of the energetic material.

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