Which of the following are orifice plate designs?
The most common design is the thin concentric orifice plate (Answer A), which operates in the turbulent flow regime. Eccentric (Answer C) and segmental (Answer F) orifice plates can handle similar applications for fluids with solids in liquid or liquids in gas.
Other designs were developed to handle applications in which the previously mentioned designs could not be used. Conical (Answer B) and quadrant (Answer E) orifice plates can operate at relatively low Reynolds numbers. Integral orifice plates (Answer D) are used to measure small flow rates.
Additional complicating factors
Most of the research on differential pressure flowmeters in the last 90 years was performed on thin, concentric orifice plates, thus the flow coefficients and equations associated with concentric orifice plates are quite good. Other orifice plate designs will likely result in inferior performance.
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