Pump Efficiency

Total pump efficency, abbreviated as ηtp (Greek symbol eta), a dimensionless number, is the effectiveness with which a pump converts input power into the desired output in the form of hydraulic energy.  Pumps are devices designed to move fluids from one place to another.  They are commonly used in various industries for applications such as water supply, irrigation, oil and gas extraction, and manufacturing processes.  The efficiency of a pump determines its overall performance and energy consumption.

The efficiency of a pump depends on various factors, including the design of the pump, its size, operating conditions, and specific characteristics of the fluid being pumped.  Pump efficiency can vary significantly depending on the type of pump, such as centrifugal, reciprocating, or rotary pumps.  In practice, pump efficiency is influenced by several factors that can cause energy losses, including internal friction, mechanical losses, hydraulic losses, and inefficiencies in the pump's design or operation.  These losses contribute to a decrease in overall efficiency, resulting in lower hydraulic power output compared to the mechanical power input.

High pump efficiency is desirable as it indicates that the pump is converting a larger proportion of the supplied energy into useful hydraulic power, leading to lower energy consumption and reduced operating costs.  Improving pump efficiency can be achieved through proper pump selection, regular maintenance, optimizing operating conditions, and utilizing advanced pump technologies.  It's important to note that pump efficiency should be evaluated under specific operating conditions, as it can vary depending on the pump's operating point on its performance curve.  The manufacturer's pump curve provides information about the pump's efficiency at different flow rates and heads, enabling users to select the most efficient operating point for their specific application.

 

Pump Efficiency formula
\( \eta_p =  ( P_o \;/\; P_i ) \; 100 \)     (Pump Efficiency) \( P_o =   \eta_p \; P_i \;/\; 100 \) \( P_i =   P_o \; 100 \;/\; \eta_p \)
Symbol	English	Metric
\( \eta_p \)  (Greek symbol eta) = pump efficiency	\(dimensionless\)
\( P_o \) = hydraulic power outout	\(lbm-ft^2 \;/\; sec\)	\(kg-m^2 \;/\; s\)
\( P_i \) = input shaft power	\(lbf-ft \;/\; sec\)	\(J \;/\; s\)