Sigma theory, centrifuges

This approach to describing centrifuge performance has become known as the sigma theory . It provides a means for comparing the performance of sedimentation centrifuges and for scaling up from laboratory and pilot scale tests see Ambler (1952) and Trowbridge (1962). 

If the two centrifuges are arranged in parallel, each one takes one half of the total flow, Q, and the performance is compared with that of one centrifuge taking the whole of the flow. In terms of cut size, the Sigma theory (see section 7.2.2) can be used to write for the same machine (same S value) ... 

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