Utilization and Optimization of Superconducting Coil Parameters in Electromagnetic Launcher Systems

2019-06-01
Polat, Hakan
Ceylan, Doga
Keysan, Ozan
The utilization of external field windings in electromagnetic launchers provides an additional electromagnetic field between the rails of an electromagnetic launcher which increases the Lorentz force acting on the armature in the acceleration direction. However, additional magnetic field created by the conventional copper windings are very limited due to their low maximum current carrying capability. Therefore, using high temperature superconductors (HTS) with a current carrying capability up to 100 A/mm 2 for the external coils can be used to increase the magnetic field density between rails. This paper presents an optimization study for the design of two external coils with rectangular tape YBCO superconducting wire. The HTS coils are proposed to increase the efficiency of a 3 meter long launcher with 25 mm x 20 mm rectangular bore caliber. The optimization parameters are selected as the magnitude of the DC coil current, the coil position, the number of turns of the coil, and the number of coil layers. Also, the objective function of the optimization is the electromagnetic force acting on the armature, which is dependent of the rail current and B field on the armature. During the operation of the launcher and the external coils, it is critical to prevent quenching of the HTS coils due to the perpendicular and tangential magnetic field on the coils, temperature and current density of the coils. In order to estimate the quench and calculate the objective function, finite element analysis (FEA) is used in 2D. Real coded genetic algorithm (RCGA) is also used as optimization method. The results of the optimization study shows that HTS coil augmentation is feasible for small caliber railguns. The HTS coil position is limited by cryogenic chamber and rail containment dimensions. The maximum coil current is determined by the self field due to cancellation B field generated by the rails and the coils. For 500 kA rail current the force acting on the armature increases from 55 kN to 70 kN with and increase rate of 26%, a muzzle velocity increase from 1650 m/s to 1900 m/s with an increase rate of 12% and a muzzle energy increase from 160 kJ to 210 kJ with and increase rate of 25% when external HTS coil augmentation is used.

Suggestions

Hybrid CFIE-EFIE solution of composite geometries with coexisting open and closed surfaces
Ergül, Özgür Salih (2005-07-08)
The combined-field integral equation (CFIE) is employed to formulate the electromagnetic scattering and radiation problems of composite geometries with coexisting open and closed conducting surfaces. Conventional formulations of these problems with the electric-field integral equation (EFIE) lead to inefficient solutions due to the ill-conditioning of the matrix equations and the internal-resonance problems. The hybrid CFIE-EFIE technique introduced in this paper, based on the application of the CRE on the ...
Design optimization of a laser path length controller through numerical analysis and experimental validation
Fenercioglu, Tevfik Ozan; Yalçınkaya, Tuncay (IOS Press, 2019-01-01)
As an integral part of Strapdown Inertial Navigation Systems, ring laser gyroscopes (RLG) are exposed to joint loading conditions where thermal, static and dynamic loads occur simultaneously. The effects of different loading conditions on overall RLG performance should be addressed in parallel for an optimum design. A crucial aspect in this process is the development of the path length controller (PLC), consisting of a mirror, a composite piezo electric bending actuator and other motion transfer elements. T...
Exact solution of the time-dependent harmonic plus an inverse harmonic potential with a time-dependent electromagnetic field
Yuce, C (2003-12-01)
In this paper, the problem of the charged harmonic plus an inverse harmonic oscillator with time-dependent mass and frequency in a time-dependent electromagnetic field is investigated. It is reduced to the problem of the inverse harmonic oscillator with time-independent parameters and the exact wave function is obtained.
Effect of conducting containment on electromagnetic launcher efficiency
Ceylan, Doğa; Keysan, Ozan (2017-11-02)
Electromagnetic launcher, also called railgun, is a projectile accelerator which uses the electromagnetic force. Existence of solid metal containment around the rails of electromagnetic launchers, which increases the mechanical durability, affects the electromagnetic force on armature and rails. In this study, the effect of distance between non-laminated conducting containment and rails, and the effect of the lamination thickness on the efficiency of railgun are investigated. Also, the effect of magnetic an...
Optimization of a Convex Rail Design for Electromagnetic Launchers
Polat, Hakan; Tosun, Nail; Ceylan, Doga; Keysan, Ozan (Institute of Electrical and Electronics Engineers (IEEE), 2020-06-01)
A rail geometry with a convex cross section instead of a rectangular one provides a higher contact area, uniform current density, and less transition on the contact surface, and it increases the performance in electromagnetic launchers. In addition, the design of convex rails should be considered together with armature structure, the distance between rails, rail length, and parasitic masses that all have an influence on the overall efficiency and armature/rail transition. A novel complete rail and launch pa...
Citation Formats
H. Polat, D. Ceylan, and O. Keysan, “Utilization and Optimization of Superconducting Coil Parameters in Electromagnetic Launcher Systems,” 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37527.