configuration is also realized with the sensor arrangement optimal for two reflection configurations for this purpose as shown in fig4 two reflection configurations are installed at opposite positions on measurement pipe 1 through which a volumetric flow v flows bottom left acoustic transducer t 4 is arranged on measuring pipe 1 diametrically opposite to top left acoustic transducer t 1 and bottom right acoustic transducer t 2 diametrically opposite to top right acoustic transducer t 3 the first reflection configuration is realized between top left acoustic transducer t 1 and top right acoustic transducer t 3 with sound path sp 1 and the second reflection configuration between bottom right acoustic transducer t 2 and bottom left acoustic transducer t 4 with sound path sp 2 sound paths sp 1 and sp 2 each contain a reflection on the pipe inner wall opposite to the acoustic transducers the sound paths of both reflection configurations in this case lie in the same plane to realize an x configuration with the same acoustic transducers t 1 to t 4 the distances between top left acoustic transducer t 1 and top right acoustic transducer t 3 and bottom right acoustic transducer t 2 and bottom left acoustic transducer t 4 in the direction of the pipe axis must be.