1. What is a Pump Power Calculator?

Definition: This calculator estimates the power required by a pump to move fluid at a specified flow rate against a given head.

Purpose: It helps engineers and technicians properly size pumps for various applications in water supply, HVAC, and industrial processes.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P \) — Pump power (Watts)
• \( \rho \) — Fluid density (kg/m³)
• \( g \) — Gravitational acceleration (9.81 m/s²)
• \( Q \) — Volumetric flow rate (m³/s)
• \( H \) — Total dynamic head (m)
• \( \eta \) — Pump efficiency (0-1)

Explanation: The formula calculates the hydraulic power needed to move the fluid, then divides by pump efficiency to get actual power requirement.

3. Importance of Pump Power Calculation

Details: Accurate power calculation ensures proper pump selection, energy efficiency, and prevents overloading of motors.

4. Using the Calculator

Tips: Enter fluid density (1000 kg/m³ for water), gravity (9.81 m/s²), flow rate, head, and pump efficiency (typically 0.7-0.9). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical pump efficiency value?
A: Centrifugal pumps typically have 70-90% efficiency (0.7-0.9), while positive displacement pumps can reach 90% or more.

Q2: How do I convert the result to horsepower?
A: Divide Watts by 746 to get horsepower (1 HP = 746 W).

Q3: What is total dynamic head?
A: It's the total height the pump must move the fluid, including friction losses in pipes.

Q4: Why does fluid density matter?
A: More dense fluids require more power to pump at the same flow rate and head.

Q5: How do I account for motor efficiency?
A: Divide the calculated power by motor efficiency (typically 0.85-0.95) to get required electrical input power.