1. What is Centrifugal Pump Power Calculation?

Definition: This calculator estimates the hydraulic power required by a centrifugal pump based on flow rate, total head, fluid density, and pump efficiency.

Purpose: It helps engineers and technicians properly size pumps and motors for fluid transfer applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P \) — Pump power (horsepower)
• \( Q \) — Flow rate (gallons per minute)
• \( H \) — Total head (feet)
• \( \rho \) — Fluid density (pounds per gallon)
• \( \eta \) — Pump efficiency (dimensionless, 0-1)

Explanation: The formula calculates the theoretical power required to move fluid against the specified head, adjusted for pump efficiency.

3. Importance of Pump Power Calculation

Details: Accurate power calculation ensures proper pump selection, prevents motor overload, and optimizes energy consumption.

4. Using the Calculator

Tips: Enter the flow rate (GPM), total head (ft), fluid density (default 8.34 lb/gal for water), and pump efficiency (default 0.8). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the 3960 constant in the formula?
A: It's a conversion factor that combines unit conversions to give the result in horsepower (1 HP = 550 ft-lb/s).

Q2: What's a typical pump efficiency value?
A: Centrifugal pumps typically range from 0.6-0.85 efficiency, with 0.75-0.8 being common for well-designed pumps.

Q3: How do I determine total head?
A: Total head includes static head, friction losses, and pressure differences. Use our Head Loss Calculator for detailed analysis.

Q4: Does this include motor efficiency?
A: No, this calculates hydraulic power. For motor power, divide by motor efficiency (typically 0.9-0.95).

Q5: What density should I use for other fluids?
A: For fluids other than water, use their specific weight (lb/gal). For example, seawater ≈ 8.56 lb/gal, gasoline ≈ 6.0 lb/gal.