Which In-line Mixer to Use

If there are no time or length limitations, the simple pipeline uses the minimum energy. If there are limitations, then  

2 Laminar Flow. In laminar flow there is no radial mixing without a motionless mixer, mechanical in-line mixer, or a stirred tank. The choice is 

This is the optimum design. The degree of mixing is given by eqs. (7-13) and (7-14)  

at the end of 3.81 m, the CoV has been reduced from 2.06 to 0.27. That is still a high variability and probably not good enough for this application. A long tailpipe would still be required. 

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