Abstract
Muzzle voltage is an essential diagnostic tool used in both contact
resistance modeling and transition determination. However, it is
challenging to stem the necessary meanings from the collected
measurements. In this study, EMFY-3 launch experiments are used to model
muzzle voltage characteristics to understand the transition mechanism
better. These experiments have muzzle energies in the range between
1.69-2.85 MJ in ASELSAN Electromagnetic Launcher Laboratory. Six
different launch tests with various rail current waveforms that ranged
between 1.5-2.1 MA are used to investigate different scenarios. Some
parameters which affect muzzle voltage are calculated with the 3-D
Finite Element Method (FEM), i.e., rail mutual inductance
$\mathrm{L_m}$. Muzzle voltages are decomposed into
subsections; each subsection is calculated with proper models.
Simulation results are coherent with experimental measurements. Findings
are compared with previous studies, and differences are explained with
possible reasons. Even though we could not conclusively resolve which
physical quantity starts to transition, the study showed that transition
does not form a specific muzzle velocity, armature action integral, or
down-slope rail current ratio.