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4	"Transfer of a fluid from..." Transfer of a fluid from one point to another Gravity flow Pumping
5	"Laminar flow" Laminar flow: fluid travels smoothly or in regular paths Turbulent flow: fluid undergoes irregular fluctuations and mixing Factors: Velocity Pipe diameter Viscosity
6	"Positive Displacement (ex" Positive Displacement (ex. rotary lobe, piston, progressing cavity): The fluid enters a fixed, sealed cavity. As the fluid is pushed through by impellers, pistons or rollers, a vacuum is left behind, which pulls in more fluid. Constant flow rate Centrifugal: Fluid is moved by centrifugal force. Constant shut-off head pressure
7	"Shut-off head" Shut-off head: The height to which a pump will move a fluid (usually measured in feet or meters of water). The maximum head is mainly determined by the outside diameter of the pump's impeller and the speed of the rotating shaft. The higher a pump's head pressure, the more powerful the pump. Priming: Remove air from between the pump head and the fluid to be pumped.
8	"Constant flow rate (volume..." Constant flow rate (volume per minute). “Timing” or “metering” pump. Cavity is sealed, therefore no fluid flows if pump is not operating. Pumps fluids with different viscosities at the same rate Pumps fluids with particles without significant damage Pumps shear-sensitive fluids without thinning Pumps to any height (head) as long as the pump motor is strong enough. No priming required Higher cost and higher maintenance than c-pumps
9	"Flow rate cannot be precisely..." Flow rate cannot be precisely controlled, not constant. Cavity is not sealed, therefore fluid flows through pump if pump is not operating. Viscous fluids flow more slowly than nonviscous. Damages particles Damages shear-sensitive fluids Only pumps to its rated head (height). Constant shut-off head. Must be primed to remove air: - Evacuate the air in the system with a positive displacement “priming” pump operating between the pump and a closed discharge valve. - Fill the pump with liquid prior to starting it. - Use a self-priming pump that maintains a reservoir of liquid at its suction.
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