Monodimensional MHD simulation of railgun plasma armature to investigate an effect of augmenting magnetic field

Railgun is the general name of the device that utilizes the high density magnetic energy produced by the large current of 104 - 107 A, and accelerates macroscopic objects and particle groups to the superhigh velocity region of 103 - 104 m/s. The expected fields of its application are diverse. The method of fuel supply to nuclear fusion plasma transfers to so-called pellet injection method. The velocity of pellet shooting aimed at with a railgun is 5 - 10 km/s. The ablation of accelerating tube inner wall material hinders the acceleration, and how to suppress this ablation is the subject of heightening the shooting velocity. As one of the effective means to reduce ablation, there is the method using bias magnetic field. The magnetic field-biased railgun is described. The numerical calculation model for plasma and the results of analysis are reported. The one-dimensional electromagnetic fluid equation was solved for the plasma armature of a railgun, and it was shown that the accelerating force proportional to the intensity of a bias magnetic field can be obtained. (K.I.)