| 摘要 |
Cell (1) for ultrasonically measuring the rate of fluid flow is provided with two transducers (t1, t2) for generating and sensing a beam of ultrasonic waves and with three ultrasonic reflectors (r1, r2, r3) so that the ultrasonic beam between the transducers (t1, t2) is deflected three times. On the place where each time the ultrasonic transducers (t1, t2) are placed, an inner surface of a first wall (3) is formed like inclined planes (31, 31') which with respect to the cell axis (A) are situated symmetrically to two inclined planes (41, 41') of a second cell wall (4), on which inclined planes (41, 41') ultrasonic reflectors (r1 and r3), respectively, are placed. Everywhere along the cell (1) the cross section is approximately symmetrical with respect to the cell axis (A), and hence also the velocity distribution in the cell is symmetrical, whereby a more exact measurement is made possible. |
