Knowledge Center

 

Term Definition
Flow Rate (Q) Measurement of the actual flow rate generated by a specific impeller rotating at a known speed. Usually measured in gallons/minute.
Pumping Rate (Q) Measurement of the actual flow rate generated by a specific impeller rotating at a known speed. Usually measured in gallons/minute.
Specific Gravity The ratio between the density of fluid and the density of water. A dimensionless value.
Reynolds Number A dimensionless number that represents the magnitude of fluid motion or agitation generated in a mixing application. This number is used in calculating the flow and power draw in applications with viscosity levels higher than water.
Flow A measurement of the movement generated in the fluid being mixed. The pumping rate of the rotating impeller is usually regarded as a measurement of flow. Applications with high flow exhibit rapid turnover of the material, but low levels of Shear. Generally, shear and flow are inversely related.
Viscosity (Cp) A measurement of the “thickness” of a fluid. Usually measured in CentiPoise (Cp), this “thickness” is actually a measurement of the internal fluid friction (resistance to motion) of the fluid.
 
Shear A measurement of the stress produced on the fluid being mixed. Applications with high shear have areas where neighboring particles have significantly different velocities causing the intermixing of fluids, dispersing of gases, or breakdown of the cohesiveness of liquid droplets. Generally, Shear and Flow are inversely related.
Static Mixing Static mixers are tubes or pipes that contain stationary devices designed to use the kinetic flow of the material to accomplish mixing or blending.
Pharmaceutical Mixer A mixer specially designed to address the sanitary requirements of the application. Pharmaceutical mixers are commonly made from stainless steel components with various forms of polish or surface treatments to support proper sanitation and cleanup. They are usually used in closed tank applications and contain seals to prevent contamination by maintaining the integrity of the mixing vessel.
Velocity Pipe (Vp) Fluid flow velocity in a circular pipe can be calculated with Imperial or American units as Vp = 1.274 q / d2 = 0.4085 qgpm / din2 (1) where v = velocity (ft/s) q = volume flow (ft3/s) d = pipe inside diameter (ft) qgpm = volume flow (US gal./min) din = pipe inside diameter (inches)
G Value (G) 1 sec^2
Pressure Difference the difference in pressure between two points of a fluid carrying network. Pressure drop occurs when frictional forces, caused by the resistance to flow, act on a fluid as it flows through the tube.