Numerical study of MHD instabilities in Liquid Metal Batteries


Numerical study of MHD instabilities in Liquid Metal Batteries

Weber, N.; Barry, L.; Galindo, V.; Grants, I.; Stefani, F.; Weier, T.

Nowadays, liquid metal batteries (LMBs) are considered as one promising device for storing electricity on the short and medium time scale. Built as a stable density stratification of two metals separated by a liquid salt electrolyte, liquid metal batteries offer comparatively very high current densities as well as a potentially superior live time, compared to solid batteries. Bearing in mind the low material price, LMBs may provide cheap power as well as energy, by simply upscaling the battery. This is where magnetohydrodynamics come into play. Currents in the order of kilo-amperes will induce fluid instabilities with the potential of short-circuiting the fully liquid battery. Beside of thermal convection and electro-vortex flows, surface instabilities, as known from aluminum smelters, and the kink-type Tayler instability (TI) are of particular significance.

We present a numerical model, based on the open source CFD library OpenFOAM which is able to simulate the Lorentz force induced fluid flow in LMBs. Starting with single phase simulations, the model shows good correspondence with a recent Tayler instability experiment. Further studies lead to a comprehensive characterization of the TI in liquid metal batteries and to a number of countermeasures for taming it. The influence of the current collectors and feeding cables of the battery is investigated, as well. Finally, first results of multiphase simulation are presented, particularly with regard to the deformation of the thin electrolyte layer.

Keywords: OpenFOAM Tayler instability simulation liquid metal battery

  • Lecture (Conference)
    9th PAMIR International Conference, 16.-20.06.2014, Riga, Lettland
  • Contribution to proceedings
    9th PAMIR International Conference, 16.-20.06.2014, Riga, Lettland

Permalink: https://www.hzdr.de/publications/Publ-19677
Publ.-Id: 19677