Abstract: A method for measuring the fluid properties of a sequence of fluids, including at least a first fluid and a second fluid. The methods utilize a monitoring assembly, having a fluid-properties measurement device that includes a resonator, and a set of resonator extensions, each one adapted to attach to the resonator in a manner such that the resonator's response to excitation is affected by immersion of the resonator extension. In the method a first one of the resonator extensions is attached to the resonator and the fluid-properties measurement device is used to measure at least one fluid property of the first fluid. Then he first one of the resonator extensions is removed from the resonator and a second one of the resonator extensions is attached to the resonator. Finally, the fluid-properties measurement device is used to measure at least one fluid property of the second fluid.

Abstract: A resonant sensor 1908 is used to determine fluid properties, the resonant sensor 1908 comprising a resonator 108 defining a lengthwise axis and having a central vibrational node (140), and a pair of opposed lengthwise end-portions (125); a support structure including a frame (115) and a set of flexible supports (110) extending from the frame to the central vibrational node and thereby supporting the resonator at the lengthwise midpoint; a driving and sensing assembly, adapted to drive the resonator to resonant motion and to sense resultant motion of the resonator and producing a motion sensed signal, responsive thereto; and a control and signal processing network adapted to control the driving and sensing assembly to drive the lengthwise end-portions in rotation about the lengthwise axis, in opposed rotational directions, and responsive to the motion sensed signal to determine at least one fluid property of a fluid under test in response to the motion sensed signal.

Abstract: A resonant sensor 1908 is used to determine fluid properties, the resonant sensor 1908 comprising a resonator 108 defining a lengthwise axis and having a central vibrational node (140), and a pair of opposed lengthwise end-portions (125); a support structure including a frame (115) and a set of flexible supports (110) extending from the frame to the central vibrational node and thereby supporting the resonator at the lengthwise midpoint; a driving and sensing assembly, adapted to drive the resonator to resonant motion and to sense resultant motion of the resonator and producing a motion sensed signal, responsive thereto; and a control and signal processing network adapted to control the driving and sensing assembly to drive the lengthwise end-portions in rotation about the lengthwise axis, in opposed rotational directions, and responsive to the motion sensed signal to determine at least one fluid property of a fluid under test in response to the motion sensed signal.

Abstract: A fluid density measurement device that includes a housing, defining a chamber and an aperture; a resonator having length that is at least 5 times greater than its smallest diameter and having a longitudinal axis and a nodal plane, transverse to the longitudinal axis. The resonator further includes a tube having a first end and a second end; a second-end closure, closing the second end; and a drive rod centrally attached to the second-end closure and extending to the tube first end. Further, the device includes a resonator transducer assembly and the resonator is sealingly joined to the aperture at the nodal plane, so that an enclosed portion extends into the chamber and an exposed portion extends outside of the chamber, and wherein the chamber tends to assume the temperature of the exposed resonator portion, causing the resonator to be isothermal.

Abstract: A method of measuring the amount of corrosion of a target material caused exposure to a fluid, over a period of time, utilizing a corrosion measuring device, including a resonator having a first surface area made of a material having a corrosion profile like that of the target material and having a second surface area made of material having a corrosion profile unlike that of the target material; and a transducer assembly, positioned to drive the resonator and sense resultant resonator motion, thereby producing a sense signal. In the method, the resonator is exposed to the target fluid over the period of time and the sense signal is analyzed over the period of time to determine changes in how the resonator responds to being driven by the transducer assembly, over time.

Abstract: A fluid density measurement device (8) that includes a housing (54), defining a chamber (18) and an aperture; a resonator (10?) having length that is at least 5 times greater than its smallest diameter and having a longitudinal axis and a nodal plane, transverse to the longitudinal axis. The resonator further includes tube (44) having a first end and a second end; a second-end closure (52), closing the second end; and a drive rod (48) centrally attached to the second-end closure and extending to the tube first end. Further, the device includes a resonator transducer assembly (22) and the resonator is sealingly joined to the aperture at the nodal plane, so that an enclosed portion (10A?) extends into the chamber and an exposed portion (10B?) extends outside of the chamber, and wherein the chamber tends to assume the temperature of the exposed resonator portion, causing the resonator to be isothermal.

Abstract: A fluid properties measurement device, including a magnetically excited and sensed resonator and a resonator electromagnetic excitation assembly, including an excitation coil driven by an electrical network, electrically connected to the excitation coil. The excitation coil is positioned so that a varying magnetic field produced by the excitation coil will drive the resonator in a pattern of resonating movement that has predetermined characteristics. Also, an electromagnetic sensing assembly, including a gradiometric sense coil is positioned so that an electromagnetic field originating due to movement of the resonator in a pattern having the predetermined characteristics, will create a time-varying gradient across the sense coil. Finally, a signal sensing electrical network is electrically connected to the sense coil.

Abstract: A resonator that includes an elastic tube defining an interior surface and a conductor threaded through the elastic tube. Solid material fills space between the conductor and the elastic tube interior surface, such that motion of the conductor is directly transferred to the elastic tube. In a preferred embodiment, the elastic tube is electrically conductive and said solid material insulates said conductor from said elastic tube.

Abstract: A method of measuring the amount of corrosion of a target material caused exposure to a fluid, over a period of time, utilizing a corrosion measuring device, including a resonator having a first surface area made of a material having a corrosion profile like that of the target material and having a second surface area made of material having a corrosion profile unlike that of the target material; and a transducer assembly, positioned to drive the resonator and sense resultant resonator motion, thereby producing a sense signal. In the method, the resonator is exposed to the target fluid over the period of time and the sense signal is analyzed over the period of time to determine changes in how the resonator responds to being driven by the transducer assembly, over time.

Abstract: A method for measuring the properties of a fluid that uses a torsionally resonant structure having a base structure; at least two parallel tines affixed to the base structure and projecting in the same direction from the base structure; and wherein the base structure is sufficiently compliant as to mutually couple the tines so that they behave as a single resonator when the tines are driven in synchronized manner. The torsionally resonant structure is immersed in the fluid to be measured and a tine driving mechanism is used to drive the tines torsionally. A tine movement sensing mechanism form measurements of tine movement response to the driving mechanism and the measurements of tine movement to form measurements of fluid properties.

Abstract: A fluid properties measurement device includes a symmetric resonant element having a first mass and a second mass, balanced to the first mass and coupled to the first mass by a torsional spring, having a nodal support between the first mass and the second mass. Also, a chamber having at least one opening accommodates the first mass, free of mechanical constraint and a driving and sensing assembly, is adapted to drive the first mass in torsion and sense resulting torsional movement of the first mass. The torsional spring passes through the opening which is sealed about the torsional spring at the nodal support and the second mass is free to be placed into a fluid, for fluid property measurements.

Abstract: A fluid properties measurement device, including a magnetically excited and sensed resonator and a resonator electromagnetic excitation assembly, including an excitation coil driven by an electrical network, electrically connected to the excitation coil. The excitation coil is positioned so that a varying magnetic field produced by the excitation coil will drive the resonator in a pattern of resonating movement that has predetermined characteristics. Also, an electromagnetic sensing assembly, including a gradiometric sense coil is positioned so that an electromagnetic field originating due to movement of the resonator in a pattern having the predetermined characteristics, will create a time-varying gradient across the sense coil. Finally, a signal sensing electrical network is electrically connected to the sense coil.

Abstract: A resonator that includes an elastic tube defining an interior surface and a conductor threaded through the elastic tube. Solid material fills space between the conductor and the elastic tube interior surface, such that motion of the conductor is directly transferred to the elastic tube. In a preferred embodiment, the elastic tube 14 is electrically conductive and said solid material insulates said conductor from said elastic tube.

Abstract: A method of measuring properties of a fluid that uses a conductor electrically connected to a current source. A magnetic field is created about the conductor and the conductor is introduced into the fluid medium. A current waveform, having a frequency, is periodically passed through the conductor, so as to cause the conductor to move, due to force exerted on the conductor from interaction of the current and the magnetic field. The conductor movement is sensed, producing a sense signal that is amplified into an amplified sense signal. The phase relationship between the current waveform and the amplified sense signal is measured and the current waveform frequency is adjusted to create a phase lock loop. The frequency when the phase lock loop is in lock state is measured as the phase between the excitation and the measured sense signal is varied, and fluid properties are calculated from the measured frequencies.

Abstract: A fluid properties measurement device includes a symmetric resonant element having a first mass and a second mass, balanced to the first mass and coupled to the first mass by a torsional spring, having a nodal support between the first mass and the second mass. Also, a chamber having at least one opening accommodates the first mass, free of mechanical constraint and a driving and sensing assembly, is adapted to drive the first mass in torsion and sense resulting torsional movement of the first mass. The torsional spring passes through the opening which is sealed about the torsional spring at the nodal support and the second mass is free to be placed into a fluid, for fluid property measurements.

Abstract: A method for measuring the properties of a fluid that uses a torsionally resonant structure having a base structure; at least two parallel tines affixed to the base structure and projecting in the same direction from the base structure; and wherein the base structure is sufficiently compliant as to mutually couple the tines so that they behave as a single resonator when the tines are driven in synchronized manner. The torsionally resonant structure is immersed in the fluid to be measured and a tine driving mechanism is used to drive the tines torsionally. A tine movement sensing mechanism form measurements of tine movement response to the driving mechanism and the measurements of tine movement to form measurements of fluid properties.