Hydrodynamic lubrication analysis of curved conductive liquid conducting film at rail-armature interface

In the process of electromagnetic orbit launching armature, the high temperature and voltage generated by millisecond level pulsed high current cause the lower melting point armature to undergo ablation, resulting in a conductive liquefaction layer. As a typical combination of Coulter and Hartmann flows in fluid mechanics, it is affected by viscous and electromagnetic forces, and the mechanism is complex. Moreover, due to the non-uniformity of ablation, the shape of the liquefaction layer is relatively fuzzy. This article uses common curve types, namely upper and lower opening parabolas and linear slopes, to derive the fluid Reynolds equation of the conductive liquefaction layer. Combined with the analytical equation of the lubrication assumption of the liquefaction layer, a curved conductive liquefaction layer model is established. This article obtains the pressure, velocity and other characteristics of the liquefaction layer, compares and analyzes the hydrodynamic lubrication characteristics of conductive liquefaction layers of different shapes during electromagnetic emission, and finally verifies the liquefaction layer model from the perspective of heat transfer equations to further calibrate the accuracy of the model. The conclusion indicates that the liquefaction layer with an upward opening parabola is more in line with the physical laws, phenomena, and characteristics of electromagnetic orbit launch devices during the ablation process.