COMAG-III: a 2-D MHD code for helical CMF generators

COMAG-III is a two-dimensional MHD code which was constructed to study the characteristics of compressed magnetic field generators which incorporate a helically wound output coil. The code is an improved and generalized version of COMAG-I, which was based on a self-consistent coupling of an Eulerian material response treatment with a magnetic field solver which included non-linear diffusion. COMAG-I also included Joule heating, Lorentz forces, a circuit equation to couple to an external load, a model for explosive burn, a detailed equation of state with a mixed phase capability, and a treatment of fracture and spall. In addition to these capabilities, COMAG-III can treat coils with turn-splitting (a technique used to reduce heating effects), and armatures having an arbitrary shape; it also can now include up to ten different materials and has a more general variable zoning capability. Sample results are described.