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Figure 2: Rapid mix sizing algorithm for lower flow rates with 20 cm through micro-mixer and no constraints 
The results show that above that with each pipe size and macro-mixing size, we have high head losses through the macro-mixing orifice which will increase to levels greater than 20 cm and hence give most of the head loss through the micro-mixing orifice.
The algorithm can be summarized in these following steps:
1. Determine the inner pipe size given the flow-rates, maximum pressure drop (20 to 50 cm). total minor loss coefficients, and the available pipe sizes. The user also sets a constraint or limit for the macro-mixing orifice head loss.
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