Electronic edition ISSN 1574-0579

Seawater magnetohydrodynamic pumps and thrusters: experiment, model and upscaling

Y. Delannoy , I. Montero , A. Zapata , N. Machicoane

Univ. Grenoble Alpes, CNRS, Grenoble INP, LEGI, 38000 Grenoble, France

Abstract
Naval magnetohydrodynamic (MHD) propulsion is faced with the high level of Joule dissipation associated with the low electrical conductivity of seawater, reducing the efficiency of the pump at the heart of an MHD thruster. An MHD pump experiment is discussed in this paper, together with its CFD modelling. A simple analytical model is also written for conduction MHD pumps, then for a boat equipped with such a pump working as an MHD thruster. The numerical and analytical results are compared to our pump experiment and to a small-scale boat model. By upscaling, we show how strong should be the magnetic field, and how large the MHD channel to obtain a given efficiency for the pump or a given cruise speed for the boat. Tables 2, Figs 8, Refs 7.