Baffles increased power requirements

In this regime, baffles are fully effective and they can increase the required stirring power by a factor as great as 10. This is illustrated in Fig. 24 for a vessel containing the blade stirrer with (curve cs) and without (curve c) baffles. 

Baffles have no effect in the laminar flow regime, but for high Reynolds numbers the effect is pronounced, as shown in Figure 3.4.10 for the example of a blade stirrer. In general, the power requirements increase if baffles are used. 

Note that a 10,000-fold increase in viscosity increases the power by only about 60 percent over that required by the baffled tank operating on the low-viscosity liquid. 

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