However, in some instances, submersible pumps are used to handle liquids whose viscosity is greatly different from water. Viscous fluids have high internal resistance to flow. Consequently, the frictional losses and disk friction are increased which results in low head and high brake horsepower. Viscosity also has an effect on leakage losses and it has been found that the viscosity reduces the capacity of a pump at the best efficiency point. Figure 4 - 6, shows an example of how a centrifugal pump curve changes due to the effects of moderate to high viscosities.
Gas can reduce viscosity.
Viscous fluid can be produced with rec. Mixed RGS flow stages perform better than radial. Temperature rise in pump High viscosity - reduces pump eff. Heat manifested as fluid heating. AutographPC includes lab -derived viscosity correction factors for all Centrilift pumps.