| 摘要 |
An elongated stop 1 reaching across the interfaces is mounted vertically inside tank 2. A transceiver 3 is mounted against the tank body and moved parallel to the stop. Discrete changes in the propagation speed of sound between the transceiver and the stop are used to locate the interfaces. Alternative arrangements include: replacing the movable transceiver with a number of fixed transceivers (fig 2); mounting a stop and a transceiver in the same movable construction (8, fig 2) to be immersed in the tank; and fixing a vertical pipe (10, fig 2) to the outside of the tank with transceiver device placed against the pipe and one wall of the pipe acting as a stop. |
