Finite Element Analysis of Magnetic Field Single-Turn Systems
Modelling of pulsed magnetic systems has extensive application in the optimisation of electromagnetic metal forming as well as in pulsed ultrahigh field generation systems. This paper presents a detailed three-dimensional finite element analysis model to be used in such power systems and compares simulated solutions with accurate experimental data.
Megagauss magnetic field generation in single-turn coils: new frontiers for scientific experiments
We report on the design and performance of a megagauss generator at the Humboldt High Magnetic Field Centre. The installation uses the fast capacitor discharge into single-turn coils to produce microsecond pulses of 260 T in 8 mm diameter suitable for low-temperature experiments and 310 T in 5 mm diameter. Simple concepts are applied to substantiate crucial design principles for the generator and the choice of components. The implementation of a high-power/low-inductance circuit operated at 60 kV and other technical questions are discussed in detail. The analysis of experimental field and current data is based on numerical simulations of the magnetic pressure and the nonlinear flux diffusion. It was carried out in order to investigate the limitations and characteristics of the Berlin generator in particular and the single-turn coil technique in general. The paper focuses primarily on field, generator and coil parameters, which can be used for performing routine, reproducible scientific experiments at low temperatures.
Heat Recovery Systems
Geothermal energy is recovered from an underground zone of relatively hot strata via a borehole into which is inserted a heat pipe system containing a working fluid, the heat pipe system comprising an assembly of two tubes in concentric relation, the inner tube being constituted by a relatively small diameter capillary for the return of working fluid to the vicinity of the zone of the relatively hot strata. The working fluid is preferably assisted in its return under gravity by means of a pump. The system includes heat exchange means operable to recover thermal energy from the working fluid. A third and outermost tube may be used to reduce heat losses, this third tube enclosing the two tubes over all but that part of their length which is in the zone of relatively hot strata.