Ultrasonic flowmeter and method for operating an ultrasonic flowmeter

An ultrasonic flowmeter, comprising:

• a measuring tube;
• a first ultrasonic transducer array;
• a second ultrasonic transducer array;
• and
• a control and evaluation unit,
• wherein a medium flows through the measuring tube during operation,
• wherein the first ultrasonic transducer array and the second ultrasonic transducer array are arranged on the measuring tube at a distance from one another as viewed in the direction of flow,
• wherein the control and evaluation unit is connected to the first ultrasonic transducer array and to the second ultrasonic transducer array,
• wherein, in a first operating state, the first ultrasonic transducer array is designed at least as an ultrasonic stimulator for the excitation of a guided ultrasonic wave which is propagated through the medium during operation, and the second ultrasonic transducer array is designed at least as an ultrasonic receiver for receiving the ultrasonic wave,
• wherein the first ultrasonic transducer array has at least two transducer elements,
• wherein the least two transducer elements is arranged on a first measuring tube circumference,
• wherein the second ultrasonic transducer array has a least two transducer elements, wherein the least two transducer elements is arranged on a second measuring tube circumference, and
• wherein the transducer elements are small in comparison with the measuring tube circumference.