Thermal Measurement Experiments and Transient Temperature Distribution of Rapid-Fire Augmented Electromagnetic Railgun

The large pulse current and high-speed sliding can raise the bulk heat in the electromagnetic rail launcher (EMRL) during each shot. It is very important to quantitatively analyze and measure the transient temperature distribution for the engineering application. In this article, the temporal–spatial distribution of the rail transient temperature rise is measured at different velocities by establishing the transient temperature measurement system. The distribution characteristics of Joule heat, resistance Joule heat, and friction heat in rail are analyzed that based on the transient characteristic of contact resistance and contact motion by using the experimental data of muzzle voltage, rail current, and armature movement displacement. Second, the temporal–spatial temperature rise is analyzed under the loads of Joule heat, resistance Joule heat, and friction heat where the armature arrives near the rising edge of pulse current under single-shot and rapid-fire. The results show that the peak of temperature rise at the breech of the railgun. Finally, the experimental data measured by the platinum resistor temperature sensor in the tests of single shots under different velocity. The experimental results agree well with the simulation results, except for experimental temperature rise at the muzzle of rail is higher. The most probable cause of the sudden temperature rise is the effect of muzzle transient arc. These conclusions show that the breech of rail is the key part of thermal management, and the influence of the heat generated by muzzle arc on the distribution of rail temperature rise cannot be ignored. This article provides a theoretical basis for the thermal design management and having guiding signification to the engineering application of the EMGL.