Magneto-Hydrodynamics (MHD)
Magneto-hydrodynamics (MHD) is the study of the behavior of electrically conducting fluids, such as plasmas, liquid metals, or saltwater, under the influence of magnetic and electric fields. By applying magnetic fields, MHD can control fluid flow, enabling applications in energy generation, propulsion, and materials processing. This principle is widely used in fusion reactors, electromagnetic pumps, and astrophysical phenomena like solar winds and planetary magnetospheres.
Liquid Metals
We analyze the flow of room and near room-temperature liquid metals in shallow, long rectangular conduits with two insulating and two perfectly conducting walls under a uniform magnetic field perpendicular to the flow direction and the insulating surfaces, focusing on moderate Hartmann numbers. A pressure gradient and Lorentz body forces may drive or oppose the flow. We derive explicit expressions for the Onsager coefficients that relate the flow rate and electric current on the one hand to the potential difference across electrodes and the pressure gradient on the other hand. We further demonstrate that these coefficients satisfy Onsager-Casimir reciprocity. These simplified expressions provide a convenient framework for analyzing, optimizing, and controlling magnetohydrodynamic (MHD) machines operating with liquid metals in applications such as power conversion, energy harvesting, pumping, actuation, valving, breaking, and sensing without moving components.
2025 Onsager Coefficients for Liquid Metal Flow in a Conduit under a Magnetic Field
Electrolytes
Electrolytes are electrically conducting fluids composed of ions dissolved in a solvent, typically water or molten salts. In the context of magneto-hydrodynamics (MHD), electrolytes conduct electricity through the movement of these charged ions rather than free electrons, as in liquid metals. When an electric current passes through an electrolyte in the presence of a magnetic field, Lorentz forces act on the ionic motion, influencing the flow behavior of the fluid. Although electrolytes generally have lower electrical conductivity than liquid metals, they are easier to handle and can be used to demonstrate fundamental MHD principles such as flow control, electromagnetic pumping, and induced circulation. Common examples include saline solutions, molten salts, and acid–base electrolytes used in electrochemical and energy conversion systems.
2022 Applications Of Magneto Electrochemistry And Magnetohydrodynamics In Microfluidics
2012 Magnetohydrodynamic Flow Of A Binary Electrolyte In A Concentric Annulus
2011 When MHD-Based Microfluidics Is Equivalent To Pressure-Driven Flow
2009 Magneto-Hydrodynamics Based Microfluidics
2006 Electrochemical Reaction With Redox In Toroidal Conduits In The Presence Of Natural Convection
2005 Magneto-Hydrodynamic Flow Of Redox Electrolyte
2002 A Stirrer For Magnetohydrodynamically Controlled Minute Fluidic Networks
2002 A Magneto-Hydrodynamics (MHD) Pump Fabricated With Ceramic Tapes