page_title: Gurney equations
section_title: Cylindrical charge
hierarchical_section_title: Gurney equations / Equations / Cylindrical charge
caption_attribution_description: English: Gurney equations ( ) explosives engineering diagram of cylindrical configuration. Cylinder of explosives with mass C wrapped by hollow flyer shell of mass M.
context_page_description: The Gurney equations are a set of mathematical formulas used in explosives engineering to relate how fast an explosive will accelerate an adjacent layer of metal or other material when the explosive detonates. This determines how fast fragments are released by military explosives, how quickly shaped charge explosives accelerate their liners inwards, and in other calculations such as explosive welding where explosives force two metal sheets together and bond them.
  The equations were first developed in the 1940s by Ronald Gurney
  and have been expanded on and added to significantly since that time. The original paper by Gurney analyzed the situation of an exploding shell or bomb, a mass of explosives surrounded by a solid shell. Other researchers have extended similar methods of analysis to other geometries. All of the equations derived based on Gurney's methods are collectively called "Gurney equations".
context_section_description: For the simplest case, a long hollow cylinder of metal is filled completely with explosives.  The cylinder's walls are accelerated outwards as described by:
  This configuration is a first-order approximation for most military explosive devices, including artillery shells, bombs, and most missile warheads.  These use mostly cylindrical explosive charges.
caption: Cylindrical charge of mass C and flyer shell of mass M
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