1. What is Pump Efficiency?

Pump efficiency (η) is the ratio of hydraulic power delivered by the pump to the mechanical power input to the pump. It indicates how effectively a pump converts the input power into useful fluid flow and pressure.

2. How Does the Calculator Work?

The calculator uses the pump efficiency formula:

Where:

• \( Q \) — Flow rate (gallons per minute, GPM)
• \( H \) — Total dynamic head (feet, ft)
• \( SG \) — Specific gravity of the fluid (unitless)
• \( HP \) — Horsepower input to the pump (HP)
• 3960 — Conversion factor (ft·lb/min per HP)

Explanation: The formula calculates what percentage of the input power is being converted to useful hydraulic work.

3. Importance of Pump Efficiency

Details: Pump efficiency is crucial for energy conservation, operating cost reduction, and proper pump selection. Higher efficiency means less energy waste and lower operating costs.

4. Using the Calculator

Tips: Enter flow rate in GPM, head in feet, specific gravity (1.0 for water), and input horsepower. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a good pump efficiency value?
A: Centrifugal pumps typically range from 40-85% efficiency. Positive displacement pumps can reach 90% or higher.

Q2: Why does specific gravity matter?
A: It accounts for fluid density. More dense fluids require more power to pump at the same flow rate and head.

Q3: How can I improve pump efficiency?
A: Proper sizing, regular maintenance, minimizing system restrictions, and using variable speed drives can help.

Q4: What affects pump efficiency?
A: Pump design, operating point relative to BEP (Best Efficiency Point), wear, viscosity, and system design all affect efficiency.

Q5: Is 100% efficiency possible?
A: No, all pumps have mechanical and hydraulic losses that prevent 100% efficiency.