Thermal loading and heat removal from a sequentially fired railgun

Data from the thermal management system of an actively cooled railgun is presented for single shot and sequentially fired operation of a 30 mm bore railgun. The data is in the form of pressure, temperature and flow measurements of water supplied to and returning from cooling channels embedded in the rails. Cooling water is driven through the rail channels just prior to, during, and after firing the railgun. Elevated water exit temperatures demonstrate the functionality of the thermal management system and provide a measure of the total thermal load applied to the rails. A simple model is developed to predict the thermal loading from two sources, ohmic heating of the rails and incident thermal flux from the plasma armature. The total thermal load predicted by the model compares favorably to the measurements for both high and low energy shots if minor allowances are made for bore surface ablation. Data from a two shot burst also compares favorably to the model.<>