Abstract

Some discussion of efforts to model plasma arcs used as armatures in electromagnetic railguns is presented. The simplest models discussed are those in which it is assumed that the plasma is steady in a frame of reference that accelerates with the arc. Results of calculations based on that assumption, indicating how various arc properties vary with position, are discussed. Limitations of these models, such as their susceptibility to various types of instabilities and their inability to describe early time behavior of the arc, are pointed out. We then indicate results from some one-dimensional, time-dependent calculations and discuss their purpose. Finally, some discussion of problems worthy of future study is presented.