PUMPING CAPACITY AND FLUID SHEAR RATES

All the power, P, applied to the systems produces a pumping capacity, Q, and impeller head, H, shown by the equation  

Q has the units of kilograms per second and //has the units of Newton meters per second. Power then would be in watts. 

The power, P, drawn by mixing impellers in the low and medium viscosity range is proportional to  

These three equations can be combined to 3deld the relationship that 

This indicates that large impellers running at slow speeds give a high pumping capacity and low shear rates since the impeller head or velocity work term is related to the shear rates around the impeller. 

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