| 摘要 |
An air monitoring system is provided for direct measurement of the volume of air flow, and its velocity and pressure in one or a composite of several air ducts. The system includes flow measuring stations which are installed in each duct as a permanent part thereof. Air moving in the duct first passes through a flow straightening section in each station which comprises a honeycomb of short, axially extending passages. Movement of the air through the straightening section eliminates turbulence in the entering air and produces substantially laminar air flow. A plurality of total pressure sensors are positioned in one or more traverses across, immediately adjacent to, and downstream of the straightening section to sense the total pressure of the flowing air. The total pressure values sensed by the several sensors are averaged by a manifold which connects with each of them. The individual total pressure sensors are so distributed as to be at the center of cross-sectional segments of the duct having equal areas. Static pressure at each station is also sensed by static pressure sensing tips, averaged and used with the total pressure to determine air flow. A tube leading directly from a remotely located manometer is connected to the manifold of the total pressure sensors at a point symmetrically arranged with respect to the total pressure sensors.
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