Magnet for a MHD linear generator

In this paper the authors analyse the performance of a magnetohydrodynamic (MHD) linear generator excited by means of various saddle shaped superconducting (sc) coils. In particular the device has been excited using: a prototype magnet, a demonstrative magnet and a commercial size magnet. The various magnet shape and size determine a quite different distribution of the magnetic flux density along the channel. To show the effects of the magnetic field shape on the device behaviour, we have simulated the fluid by means of a three-dimensional (3D) lumped parameter network representative of all major physical phenomena. The equivalent network has been determined using an innovative approach with respect to the parameter evaluation. The reliability of the proposed model has been verified using experimental data. The aim of this paper is to show the importance of the device simulation in the magnet optimization design to quantify the effects of a nonhomogeneous magnetic field