| 摘要 |
<p>A means for detecting the presence of particulate material, e.g., sand, in a fluid stream flowing through a conduit, said detection means comprising an acoustical means which is positioned on the outer surface of a substantial bend in said conduit. The detection means has a housing in which a transducer, e.g., piezoelectric means, is freely suspended. The housing is filled with oil to acoustically couple the transducer to the conduit. Particulate material in the fluid stream gives up kinetic energy upon striking the inner surface of said bend in said conduit which in turn excites the transducer to generate an output signal having a frequency component, e.g., 700 kilohertz, which is representative of the particulate material.</p> |
