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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. 

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2. Using the pipe size given, determine the orifice diameter of the macro-mixing orifice.  This is determined using the equation for minor loss coefficients for submerged orifices

3.  If the head loss through the macro-mixing orifice exceeds 2 cm, then move up to the next pipe available and recalculate the orifice size.  This step is repeated until the head loss is 2 cm or less. 

4.  Use the assigned total head loss value (20-50 cm) and maximum flow rate to determine the minor loss coefficient needed for the micro-mixing orifice.  Using the equation for minor loss coefficients for submerged orifices to determine the orifice diameter for the micro-mixing orifice.

For a flow rate of 1 L/s with 50 cm maximum head loss, we obtained an inner pipe diameter of 1.89 in and macro-mixing and micro-mixing orifice diameters of 1.64 in and 0.94 in respectively. For the case of 2 L/s with 50-cm maximum head loss, we obtained an inner pipe diameter of 2.80 in and macro-mixing and micro-mixing diameters of 2.42 in and 1.33 in respectively. There will be changes made to make this algorithm more robust and they are in process.  In the cases of higher flow-rates, it is better to transition to the waterfall rapid mix design that the research team came up with before. 

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