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The area of the small scale orifice can be either cirucular or rectangular in shape, again depending upon the plant flow rate, desired energy dissipation rate, and desired head loss through the small-scale orifice. A diagram of some possbile orifice configurations is shown below in Figure 5.
Figure 5. Possible configurations for the small scale rapid mix orifice. Which is chosen depends upon the specific plant for which the rapid mix system is being designed.
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