Circuit Balance Valve/Flow Venturi Quirk May Mean Reversed Flow

摘要

Typically, the valves have been proprietary and required the use of a particular calculating device to interpret the readings obtained. But recent changes in the design of these products have effectively made them self-contained, constant-area flow venturies, simplifying their use as a test and balance device. Once the Cv of the device is established, the changes in pressure drop can be easily calculated to find the correct final setting and flow. The use of a rotary calculator, chasing a constantly changing orifice, has been pretty much eliminated.