Electrostatic Relativistic Fluid Models of Electron Emission in a Warm Diode

A semianalytic fluid model has been developed for characterizing relativistic electron emission across a warm diode gap. We demonstrate the use of this model in: 1) verifying multifluid codes in modeling compressible relativistic electron flows (the EMPIRE-Fluid code is used as an example); 2) elucidating key physics mechanisms characterizing the influence of compressibility and relativistic injection speed of the electron flow; and 3) characterizing the regimes over which a fluid model recovers physically reasonable solutions.