Abstract: A magnetic-inductive flowmeter includes a measuring tube for guiding an electrically conductive medium, a magnetic field device, a magnetic field guiding device, and a control and evaluation unit. The magnetic field device includes at least three coils for generating a magnetic field through the measuring tube. The magnetic field guiding device guides the magnetic field with at least three measuring electrodes for tapping a measurement voltage induced in the medium. The control and evaluation unit generates the magnetic field by energizing the coils and evaluates the measurement voltage. The coils are distributed over a circumference of the magnetic field guiding device, which acts a coil core in a region of the coils, so that the coils are arranged with their coil longitudinal axes in the circumferential direction with respect to the measuring tube. Each of the measuring electrodes is arranged between two coils in the radial direction.

Abstract: A flowmeter for a multi-phase medium includes an ultrasonic transducer, a permittivity sensor, and a controller. The ultrasonic transducer converts electrical transmitting signals into ultrasonic transmitting signals, radiates them into the measurement volume, receives reflected ultrasonic receiving signals from the measurement volume, and converts the ultrasonic receiving signals into electrical receiving signals. The controller determines a reflection energy of the ultrasonic receiving signals from the measurement volume using the electrical receiving signals and distinguishes between, on the one hand, the water and the oil and, on the other hand, the gas in the measurement volume using the reflection energy. The controller determines a permittivity of the medium in the measurement volume using the permittivity sensor and distinguishes between, on the one hand, the water and, on the other hand, the oil and the gas in the measurement volume using the permittivity.

Abstract: An ultrasonic transducer for an ultrasonic flowmeter includes a transducer housing and a transducer element arranged in the transducer housing for generating and/or receiving ultrasonic signals at least in a useful frequency range of the ultrasonic transducer. The transducer housing has an ultrasound window in the region of the transducer element for transmitting the ultrasound signals between the interior and the exterior of the transducer housing. The transducer housing has a fastening section for fastening the ultrasonic transducer to a measuring tube. The transducer housing extends with a transition section between the ultrasound window and the fastening section. The transition section of the transducer housing has, in an attenuation region, a phononic crystal with an acoustic band gap in the useful frequency range, so that the transmission of ultrasonic signals in the useful frequency range between the ultrasound window and the fastening section is at least attenuated.

Abstract: An ultrasonic flowmeter having a measuring tube, a control unit, at least one first ultrasonic measuring unit and a second ultrasonic measuring unit, the measuring tube having a measuring tube interior and a measuring tube longitudinal axis, wherein each of the ultrasonic measuring units is arranged on the measuring tube, wherein each ultrasonic measuring unit has a first ultrasonic transducer and a second ultrasonic transducer, the first and the second ultrasonic transducers spanning a sound measuring section with a sound axis. The sound measuring section and the sound axis penetrate the measuring tube interior for carrying out ultrasonic measurements. To provide an ultrasonic flowmeter for reliable measurement of a multi-phase medium, the sound axis of the first ultrasonic measuring unit and the sound axis of the second ultrasonic measuring unit span a sound measuring plane which extends substantially parallel to the longitudinal axis of the measuring tube.

Abstract: A computer-implemented method for operating a shut-off device for a fluid includes: using a mathematical model to calculate a current static fluid pressure at a location of interest within a shut-off device as a function of at least one measured state variable of the fluid; determining a vapor pressure of the fluid; comparing a current static fluid pressure with a cavitation limit value which is dependent on a vapor pressure of the fluid; and in the event of the calculated current static fluid pressure falling below the cavitation limit value dependent on the vapor pressure of the fluid, signaling the presence or expected presence of cavitation at the location of interest of the shut-off device. A related shut-off device is also disclosed.

Abstract: An ultrasonic flowmeter includes first and second ultrasonic transducers and a control and evaluation unit connected thereto. The first and/or second ultrasonic transducer is/are an ultrasonic transmitter and/or an ultrasonic receiver. The first and second ultrasonic transducers are arranged on a measuring tube in such a way that a signal path is formed therebetween, and such that a measuring signal emitted by the ultrasonic transmitter runs via the signal path to the ultrasonic receiver. The first and/or second ultrasonic transducer has array to of at least two active elements. At least one ultrasonic transducer with an array of at least two active elements is formed as a wedge transducer. At least two active elements of the array arranged on the first ultrasonic transducer, and/or at least two active elements of the array arranged on the second ultrasonic transducer, are separately controllable by the control and evaluation unit.

Abstract: A method for calibrating a temperature measuring unit based on ultrasound measurement includes: establishing an empirical functional relationship between the medium temperature of a medium to be measured and the velocity of sound of a measurement signal passing through the medium to be measured; capturing at least the velocity of sound of the measurement signal, the temperature measured by means of a temperature sensor, and the time variation of the sensor temperature at at least two measuring points, wherein the at least two measuring points have a different medium temperature; determining the medium temperature from the measured temperature, taking into account the time variation of the sensor temperature, so that at least two pairs of values and exist; running a compensating curve through the pairs of values which corresponds to the empirical functional relationship; and storing the functional relationship.

Abstract: A flow sensor for a multi-phase medium flowmeter has a sensor carrier, and the sensor carrier has at least one first sensor array. The at least one first sensor array has a first permittivity sensor for determining a first permittivity of a multi-phase medium, a second permittivity sensor for determining a second permittivity of the medium, a density sensor for determining a density of the medium, and a first sensor axis. The first permittivity sensor, the second permittivity sensor, and the density sensor are arranged on the sensor carrier along the first sensor axis, and the first permittivity sensor and the second permittivity sensor are spaced apart with a permittivity sensor distance.

Abstract: A measuring device has a flowmeter, an inlet tube and an outlet tube. The flowmeter has a measuring tube that is connected to the inlet tube and to the outlet tube. To provide a measuring device that allows for measurements using a flowmeter, in particular of the liquid components of medium in the measuring tube, independent of whether the medium is made to flow or is stagnant, wherein the measuring tube is completely filled at least with the liquid components of the medium when the medium is stagnant the inlet tube, the measuring tube and the outlet tube form a siphon, wherein the siphon is designed and aligned in respect to the vector of the gravitational field of the earth so that, when a medium initially flows through the siphon and then the flowing of the medium stops, the measuring tube is completely filled with the stagnant medium.

Abstract: An ultrasonic flowmeter having a measuring tube, a control unit, at least one first ultrasonic measuring unit and a second ultrasonic measuring unit, the measuring tube having a measuring tube interior and a measuring tube longitudinal axis, wherein each of the ultrasonic measuring units is arranged on the measuring tube, wherein each ultrasonic measuring unit has a first ultrasonic transducer and a second ultrasonic transducer, the first and the second ultrasonic transducers spanning a sound measuring section with a sound axis. The sound measuring section and the sound axis penetrate the measuring tube interior for carrying out ultrasonic measurements. To provide an ultrasonic flowmeter for reliable measurement of a multi-phase medium, the sound axis of the first ultrasonic measuring unit and the sound axis of the second ultrasonic measuring unit span a sound measuring plane which extends substantially parallel to the longitudinal axis of the measuring tube.

Abstract: A method for operating a flowmeter for determining the flow of a multiphase medium flowing through a measuring tube using a first and a second measuring device, one of which operates on a tomographic measuring principle and one of which uses a measuring principle based on nuclear magnetic resonance. The first measuring device operates in a different manner from the second measuring device, e.g., using a measuring device operating on the measuring principle of pre-magnetization contrast measurement and having a pre-magnetization section with a constant magnetic field. The magnetic field has at least one component perpendicular to the direction of flow of the multi-phase medium and is generated by using magnetic field generating elements, which are arranged around the measuring tube. Additionally, an assembly for exciting nuclear spin by a RF excitation pulse or a RF excitation pulse sequence is part of the measuring device.

Abstract: A method for operating a nuclear-magnetic flowmeter in which, when determining a velocity of the medium through a measuring tube, the dependency on properties or the state of a medium is at least reduced. The method exciting a first volume of the magnetized medium flowing at a first velocity within a first measuring section to nuclear-magnetic resonances and a first signal sequence is formed characterizing the nuclear-magnetic resonances of the medium in the first volume, and then, exciting a second volume of the magnetized medium flowing at a second velocity within the first measuring section is excited to nuclear-magnetic resonances and a second signal sequence is formed characterizing the nuclear-magnetic resonances of the medium in the second volume. A quotient sequence is determined from each of the first and second signal sequences, and the first velocity and/or the second velocity is/are determined using the quotient sequence.

Abstract: A method for operating a nuclear magnetic flowmeter for determining the flow of a slug flow medium flowing through a measuring tube, with which “tuning” parameters and “matching” parameters are set for a slug zone a film zone, reflected power is measured over time. If the reflected power in a system set for slug zone is low for the slug zone and high for the film zone and if the reflected power in a system set for film zone is low for the film zone and high for the slug zone, relative dwell time of the slug zone and the film zone in the RF coil and the relative frequency of the slug zones and film zones in the flowing medium are determined using the reflected power with a jump in the value of the reflected power from a high value to a lower value used to trigger measurement initiation.

Abstract: A method for measuring the flow rate of a multi-phase medium flowing through a measuring tube using a nuclear magnetic resonance flow meter can be used to measure the flow rate of a multi-phase medium in a simplified manner. For this purpose, a measuring device is used which implements, at the end of each pre-magnetization path, 2D tomography in the measurement tube cross-sectional plane with stratification in the z direction; the measurement tube cross-sectional plane is subdivided into layers that are thin compared to the measurement tube diameter; nuclear magnetic resonance measurements are carried out in every layer to determine measurement signals, using pre-magnetization paths of different lengths; the flow rates are measured in every layer based on the measurement signals; and the time is determined from the signal ratios of the amplitudes of the measurement signals in every layer.

Abstract: A nuclear magnetic flowmeter (1) for determining the flow of a medium flowing through a measuring tube (2) having a magnetic field generator (4), a measuring unit (5) and an antennae unit (6) with an antenna (7). wherein the antennae unit (6) has at least one further antenna (11, 12), that is designed as a coil and is designed for transmitting the excitation signal to the magnetized medium (3) and for detecting the measuring signal over a further measuring section (13, 14) aligned parallel to the longitudinal axis (8) of the measuring tube and located in the magnetic field path (9), and the measuring section (10) and the further measuring section (13, 14) are different.

Abstract: A flowmeter for determining the flow of a multi-phase medium through a measuring tube has a first and a second measuring device, one of which operates on a tomographic measuring principle and one of uses a measuring principle based on nuclear magnetic resonance. The first measuring device operates in a different manner from the second measuring device, e.g., using a measuring device operating on the measuring principle of pre-magnetization contrast measurement and having a pre-magnetization section with a constant magnetic field. The magnetic field has at least one component perpendicular to the direction of flow of the multi-phase medium and is generated by using magnetic field generating elements, which are arranged around the measuring tube. Additionally, an assembly for exciting nuclear spin by a RF excitation pulse or a RF excitation pulse sequence is part of the measuring device.

Abstract: A method for operating a flowmeter for determining the flow of a multiphase medium flowing through a measuring tube using a first and a second measuring device, one of which operates on a tomographic measuring principle and one of which uses a measuring principle based on nuclear magnetic resonance. The first measuring device operates in a different manner from the second measuring device, e.g., using a measuring device operating on the measuring principle of pre-magnetization contrast measurement and having a pre-magnetization section with a constant magnetic field. The magnetic field has at least one component perpendicular to the direction of flow of the multi-phase medium and is generated by using magnetic field generating elements, which are arranged around the measuring tube. Additionally, an assembly for exciting nuclear spin by a RF excitation pulse or a RF excitation pulse sequence is part of the measuring device.

Abstract: A method for operating a nuclear magnetic flowmeter having a measuring device for determining the flow of the medium through the measuring tube, the measuring device having a magnetic field generator for generating a magnetic field permeating the medium and the measuring tube and for carrying out nuclear magnetic measurements of measuring volumes that are adjustable in position and size in the magnetic field. The nuclear magnetic measurements involve adjusting the size of the measuring volume, positioning the measuring volume, generating excitation signals for exciting the medium, transmitting excitation signals into the measuring volume and measuring echo signals caused by the excitation signals. Deposits on the inner wall of the measuring tube are determined from echo signals of all nuclear magnetic measurements assigned to the position of the measuring volume of the respective nuclear magnetic measurement and at least one abrupt change in the echo signals detected.

Abstract: A nuclear magnetic flowmeter (1) for determining the flow of a medium flowing through a measuring tube (2), having a magnetic field generator (3) having permanent magnets for generating a magnetic field interfusing the medium over a magnetic field section LM, having a pre-magnetization section LVM located within the magnetic field section LM and having a measuring device also located in the magnetic field section LM including a coil-shaped antenna (4) with the length L1 serving as a measuring antenna. At least one coil-shaped antenna (5) is provided in the pre-magnetization section LVM for generating a pulse or pulse sequence spoiling the magnetization of the medium in the direction of the magnetic field.

Abstract: A method for operating a nuclear-magnetic flowmeter in which, when determining a velocity of the medium through a measuring tube, the dependency on properties or the state of a medium is at least reduced. The method exciting a first volume of the magnetized medium flowing at a first velocity within a first measuring section to nuclear-magnetic resonances and a first signal sequence is formed characterizing the nuclear-magnetic resonances of the medium in the first volume, and then, exciting a second volume of the magnetized medium flowing at a second velocity within the first measuring section is excited to nuclear-magnetic resonances and a second signal sequence is formed characterizing the nuclear-magnetic resonances of the medium in the second volume. A quotient sequence is determined from each of the first and second signal sequences, and the first velocity and/or the second velocity is/are determined using the quotient sequence.