Abstract
An electromagnetic rail launcher is composed of two conducting rails and a projectilewith one or more brushes. Due to the magnetic field generated by the current in the rails, the
projectile is propelled by an electromagnetic force.
In order to obtain velocities up to 2000 m/s, currents reaching several MA can be
required. The armatures, ensuring the contact between the rails, are heavily heated and can be transformed into plasma, which has to be avoided. One possibility is to limit the current in the projectile, but without reducing the electromagnetic force. This can be obtained by applying an exterior magnetic field, generated by an exterior circuit. The launcher is then said to be "augmented".
The objective of this thesis is to study the consequences of the application of the
exterior magnetic field, to model the augmented launcher and to validate the model by an
experimental study.
An augmented launcher, with a length of 1.5 m and a calibre of 15 x 15 mm2, has been
constructed. The power supply consists of capacitor banks. The current in the rails has a
maximum value of 200 kA, the current in the exterior circuit has a maximum value of 300
kA. The mass of the projectiles ranges from 16.0 g to 20.9 g ; velocities between 291 m/s and
1200 m/s have been obtained.
We have proven through finite element simulation that the maximum repulsive forces
applied to the rails are much higher than those applied to the rails of the non-augmented rail
launcher. The propulsive force on the projectile has been modelled and validated. A model of
the electric circuit of the launcher is presented. It has been shown experimentally that the
augmented rail launcher is capable of accelerating projectiles, without transformation of the
solid contact in a plasma contact, up to kinetic energy levels which are much higher than
these obtained with a non-augmented launcher (an
Date of Award | 18 Oct 2004 |
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Original language | French |
Awarding Institution |
|
Sponsors | French-German Research Institute |
Supervisor | Jean-Marie Kauffmann (Supervisor) & Pascale Lehmann (Co-Supervisor) |
Keywords
- Railgun
- Augmented railgun