Liquid metal

About: Liquid metal is a research topic. Over the lifetime, 6947 publications have been published within this topic receiving 77785 citations. The topic is also known as: liquid alloy & liquid metal alloy.

Sloshing instability and electrolyte layer rupture in liquid metal batteries

Abstract: Liquid metal batteries (LMBs) are discussed today as a cheap grid scale energy storage, as required for the deployment of fluctuating renewable energies. Built as stable density stratification of two liquid metals separated by a thin molten salt layer, LMBs are susceptible to short-circuit by fluid flows. Using direct numerical simulation, we study a sloshing long wave interface instability in cylindrical cells, which is already known from aluminium reduction cells. After characterising the instability mechanism, we investigate the influence of cell current, layer thickness, density, viscosity, conductivity and magnetic background field. Finally we study the shape of the interface and give a dimensionless parameter for the onset of sloshing as well as for the short-circuit.

Multidimensional numerical modeling of heat exchangers

Abstract: A comprehensive, multidimensional, thermal-hydraulic model is developed for the analysis of shell-and-tube heat exchanges for liquid metal services. For the shellside fluid, the conservation equations of mass, momentum and energy for continuum fluids are modified using the concept of porosity, surface premeability and distributed resistance to account for the blockage effects due to the presence of heat transfer tubes, flow baffles/shrouds, the support plates, etc. On the tubeside, heat transfer tubes are connected in parallel between the inlet and outlet plenums, and tubeside flow distribution is calculated based on the plenum-to-plenum pressure difference being equal for all tubes. It is assumed that the fluid remains single-phased on the shell side and may undergo phase-change in the tube side, thereby simulating the conditions of Liquid Metal Fast Breeder Reaction (LMFBR) intermediate heat exchanges (IHX) and steam generators (SG). The analytical model predictions are compared with three sets of test data (one for IHX and two for SG) and favorable results are obtained, thus providing a limited validation of the model.

Magnetically- and Electrically-Controllable Functional Liquid Metal Droplets

Abstract: Gallium based room temperature liquid metal alloys have recently been explored to be an emerging functional material. They have attracted particular attentions in a variety of applications due to their unique properties. Many of the applications are based on the precise control over the motion of liquid metal, and yet, the fact that currently lacking the advanced and reliable controlling methods greatly hinders the potential of liquid metal to be applied in a wider range of fields. In this study, we develop an innovative approach to obtain functional liquid metal (FLM) by modifying it with copper-iron magnetic nanoparticles (Cu-Fe NPs). The magnetic modification process enables the Cu-Fe-NPs to be suspended within the liquid metal and form the FLM. The FLM exhibits similar appearance, actuating behaviors, and deformability in alkaline solutions to those of pure liquid metal alloys. Meanwhile, the magnetic modification enables the precise and rapid manipulation of the liquid metal using a magnetic field. Most importantly, for the first time, we demonstrated the precise control and climbing locomotion of the FLM with the interworking of both electric and magnetic fields simultaneously. The remarkable features of the FLM may represent vast potentials toward the development of future intelligent soft robots.

A liquid caesium field ion source for space propulsion

Abstract: Liquid metal ion sources usually employ a single point geometry for the anode either in the form of a wetted needle or a capillary. The realisation of high ion currents whilst, at the same time, maintaining a low neutral mass emission rate has necessitated a different approach. Here the authors report a Cs field ion source which is novel in that emissions issue from a multitude regularly spaced liquid cusps. These sites are anchored at the mouth of a micrometre-sized slit which forms a channel of high flow impedance through which liquid caesium is constrained to flow. The properties of this emitter have been investigated by electrical and mass-loss measurements, the latter having been performed on a sensitive dual-axis vacuum microbalance permitting independent real time measurements of the total mass emission rate and of the thrust. Some properties of the emitter may be understood from a consideration of the hydrodynamic stability where the applied electric field acts on the liquid surface at the mouth of the emitter slit. Following this, a simple viscous flow model of the emitter is given which agrees well with experiments.