Abstract: A transducer (700) of great sensitivity is disclosed which incorporates a magnetohydrodynamic (MHD) cell (738) exposed to the flow of a electrically conductive fluid (712) within a channel (704). Flexible diaphragms (722) form the ends of the channel (704) and deflect with the fluid motion. The deflection is sensed by strain gauges (724) and the signals from the MHD cell and strain gauges are processed. In addition, an MHD power generator is contemplated which generates power from a moving electrically conductive fluid, such as sea water in geophysical motion. A strong magnetic field is established normal the direction of fluid flow. Electrodes are positioned normal to both the magnetic field and fluid flow to complete a circuit to transfer the power generated by the movement of the electrically conductive fluid through the magnetic field.

Abstract: Magnetohydrodynamic (MHD) perturbation sensing apparatus. A rigid, shock resistant enclosure provides a housing having a sealed interior, in which a magnetohydrodynamic sensor and associated electronics are disposed. A hollow tubular conduit having an internal channel containing an electrically conductive fluid such as mercury or an electrolyte is of preferably ring shaped dimensions. The electrically conductive fluid is subject to perturbation-responsive movement within the ring. A very strong magnetic field is set up perpendicularly with respect to the plane occupied by the conduit by at least one pair of spaced apart magnets which have opposite poles disposed in a line generally normal to the plane of the conduit. One or more pairs of electrodes are secured to the conduit in a position normal to the magnetic field whereby to sense perturbations.

Abstract: A magnetohydrodynamic geophone for seismological detection. The geophone is of rigid shock resistant design, including a sealed, rigid generally conically shaped housing which is adapted to be firmly embedded within the ground in bedrock or the like, in or adjacent to an area to be seismologically monitored. The shock resistant housing includes an isolated interior for receiving an MHD sensor which detects the seismological vibration. The sensor includes a generally tubular conduit containing an electrically conductive fluid, preferably mercury or an electrolyte. A very strong magnetic field is set up perpendicularly with respect to the plane occupied by the conduit. An electric field is generated through the Faraday Effect in response to vibrations. Preferably the conduit is of ring shaped configuration, and the conductive fluid is continuously circulated throughout it.