Abstract: A method for operating an ultrasonic measuring device for measuring a property of a medium includes: an arrangement of at least two pair of ultrasonic transducers for emitting and receiving ultrasonic signals across a signal path through a fluid; a holding apparatus having a wall in contact with the medium and a flat wall section for holding the ultrasonic transducers; an electronic circuit configured to operate the ultrasonic transducers and to provide measured values of the property, wherein the ultrasonic transducers form Lamb oscillations in the respectively associated wall, wherein at least two pair of the at least two pair of ultrasonic transducers each excite and capture different modes of Lamb oscillations, wherein the different modes are excited in groups, wherein a time delay between temporally adjacent emissions of ultrasonic signals is shorter than a shortest propagation time of the ultrasonic signals between associated ultrasonic transducers.

Abstract: A method for operating an ultrasonic measuring device, which includes: an arrangement of ultrasonic transducers for emitting and receiving ultrasonic signals along at least two signal paths through a fluid, wherein the arrangement is held by a holding apparatus having at least one wall, wherein sections of the signal paths run through at least one of the at least one wall, wherein signal path sections of at least two signal paths in the fluid are of different length; and an electronic measuring/operating circuit configured to perform the method of, in a first method step, comparing intensities of ultrasonic signals along signal paths having signal path sections of different length in the fluid and, in a second method step, determining a damping property of the fluid and an acoustic coupling property between the wall and the fluid therefrom.

Abstract: An ultrasound instrument for detecting a measured value of a medium includes a measurement chamber having a chamber wall and a longitudinal axis; a pair of ultrasound transducers configured to transmit ultrasound signals along a signal path between ultrasound transducers of the pair through the measurement chamber and to receive ultrasound signals, wherein the signal path includes a signal reflection on a reflection surface, wherein the chamber wall in a region of the reflection surface opposite a first chamber side is configured to prevent a reflection of an ultrasound signal on a chamber outer surface of the chamber wall in the direction of the signal path, wherein the chamber wall has, in the region of the reflection surface, a maximum wall thickness which is at least a factor of 1.5 greater than a Rayleigh wavelength, associated with a central frequency, of the ultrasound signal in the chamber wall.

Abstract: An ultrasound instrument for detecting a measured value of a medium includes a measurement chamber having a chamber wall and a longitudinal axis; a pair of ultrasound transducers configured to transmit ultrasound signals along a signal path between ultrasound transducers of the pair through the measurement chamber and to receive ultrasound signals, wherein the signal path includes a signal reflection on a reflection surface, wherein the chamber wall in a region of the reflection surface opposite a first chamber side is configured to prevent a reflection of an ultrasound signal on a chamber outer surface of the chamber wall in the direction of the signal path, wherein the chamber wall has, in the region of the reflection surface, a maximum wall thickness which is at least a factor of 1.5 greater than a Rayleigh wavelength, associated with a central frequency, of the ultrasound signal in the chamber wall.