Description
Opportunity : Lawrence Livermore National Laboratory (LLNL), operated by the Lawrence Livermore National Security (LLNS), LLC under contract no. DE-AC52-07NA27344 (Contract 44) with the U.S. Department of Energy (DOE), is offering the opportunity to enter into a collaboration to further develop for commercialization its modular gradient-free shaped charge technology. Background : The simplest configuration for a shaped charge is a right circular cylinder, comprised of an annulus of explosive surrounding a thin-walled metal or other material tube (commonly referred to as the liner). When the explosive is initiated at one end, the progressing detonation will collapse the liner along the axis of the charge. The collapse process progresses along the charge at the same velocity speed as the detonation. An analytic solution exists to describe the progressive collapse of the liner and under certain conditions forms a jet of liner material in the forward direction. The resulting jet from a cylindrical collapse has a speed of twice the detonation speed and no velocity gradient from tip to tail of the jet. This simple relationship between detonation speed and jet speed, which is constant along the entire length of the charge enables the creation of a jet limited in length only by the length of the charge. The length of traditional shaped charge jets can only be increased in length by increasing the diameter as well as the length of the charge. This is a massive penalty as charge weight increase by a factor of eight to accomplish a doubling of jet length. This invention allows the jet length to be doubled with only a factor of two increase in charge weight. Description : LLNL’s modular gradient-free shaped charge uses a cylindrical charge and liner geometry, in conjunction with multiphase blast explosive (MBX) which provides a mechanism for reducing the axial rate of propagation (speed) of the detonation front to a value below that of common liner materials such as copper. This combination of MBX, copper liner, and cylindrical geometry meets the subsonic criterion for stable jet formation and allows a linear increase in jet length with a corresponding linear increase in charge weight. The resulting jet is also a constant velocity jet, no tip to tail velocity gradient, at approximately twice the detonation velocity of the MBX formulation. The MBX material used for this invention is a uniform mixture of a conventional explosive infiltrated with inert particles. The role of the particles is to disrupt the normal detonation propagation rate by forcing the detonation to propagate around the inert particulates in the mixture. In practice, detonation rates have been reduced to less than 5 km/sec in HMX based explosives, which allows stable jets to form using cylindrical liners of copper or any other material with sound speed less than the MBX detonation velocity. It is also a property of a cylindrical liner that the resulting jet speed is independent of the liner material and thus different liner materials can be incorporated in the same charge, resulting in a jet of sequential materials of different densities. The cylindrical geometry of this invention allows for the coupling together of multiple modules, each module producing a gradient-free jet at the same speed, thereby producing an arbitrarily long jet. The jet speed is not dependent on the liner material and thus different modules can incorporate different liner materials, producing a jet comprised of sequentially different materials. A particular configuration of modules can consist of a base unit which serves to initiate the detonation propagation and the formation of a jet. This base unit can be comprised of a conventional explosive driving a conventional simple shaped charge liner configuration, such as a cone or tulip geometry. The base unit is directly coupled to an MGF cylindrical module incorporating MBX, with the shaped liner of the base unit directly aligned with the cylindrical liner of the module and the detonation in the base unit directly shock initiating the MBX. Thus the added modules require no independent initiation system, as they are contact initiated directly from the base unit or prior module. Advantages : The modular aspect of this invention allows for in-field assembly of a modular components to adjust the length as well as the material(s) in a continuous jet. The modular aspect also allows for easy portability of individual modules which can be easily assembled to produce deep penetration. These features are unique to this invention. The use of a cylindrical shaped charge liner is not a new concept; however, its implementation has not been realized because of it requires an explosive with detonation speed less than the sound speed of the liner material. For common solid explosives and metal liners, this combination of material properties does not exist. So, while the theory is not new, the realization is new. LLNL’s Modular gradient-free shaped charge enables the sound speed criteria to be met, by using a heavily metal loaded explosive to drive a standard liner material. The particulate loading of the explosive has the effect of reducing the detonation speed below the sound speed of common metals such as copper, steel, aluminum, etc, thus enabling the formation of a stable jet of these liner materials. The particulate loading of the explosive serves to reduce the rate of propagation of the detonation along the axial direction of the charge, while maintaining a relatively high detonation pressure. This combination of reduced effective detonation speed without a corresponding reduction in detonation pressure results in an increased deflection angle of the liner under explosive loading, which serves to increase the diameter of the jet. Also, it is not necessary to utilize a high-density metal particulate fill in the explosive, as the operative mechanism in MBX is the obstruction of direct forward progression of the detonation. The required obstruction can be obtained by particles of any density, as long as they serve to provide sufficient obstruction to the straight-forward detonation propagation. Potential Applications : Military uses including anti-armor and anti-submarine warheads, disablement tool for explosive ordnance disposal, and render safe operations. A constant velocity jet does not undergo the particulation inherent in a stretching jet. Thus, the charge can be used in applications requiring a long standoff distance between the charge and target. Past and current uses of charges designed for gradient free operation are not modular and thus have an inherent limit to jet length and require large diameters to increase jet length. Development Status: LLNL has a published patent application covering this technology, U.S. Patent Application 15/685486. LLNL is seeking industry partners with a demonstrated ability to bring such inventions to the market. Moving critical technology beyond the Laboratory to the commercial world helps our licensees gain a competitive edge in the marketplace. All licensing activities are conducted under policies relating to the strict nondisclosure of company proprietary information. Please visit the IPO website at https://ipo.llnl.gov/resources for more information on working with LLNL and the industrial partnering and technology transfer process. Note: THIS IS NOT A PROCUREMENT . Companies interested in commercializing LLNL's modular gradient-free shaped charge technology should provide a written statement of interest, which includes the following: 1. Company Name and address. 2. The name, address, and telephone number of a point of contact. 3. A description of corporate expertise and facilities relevant to commercializing this technology. 4. Company ITAR registration expiration date. Written responses should be directed to: Lawrence Livermore National Laboratory Innovation and Partnerships Office P.O. Box 808, L-795 Livermore, CA 94551-0808 Attention: FBO 415-19 Please provide your written statement within thirty (30) days from the date this announcement is published to ensure consideration of your interest in LLNL's modular gradient-free shaped charge technology.