Centrifugal Pump Power Calculator

Pump Power Equation:

\[ P = \frac{\rho \times g \times Q \times H}{\eta} \]

Density (ρ):

kg/m³

Flow Rate (Q):

m³/s

Head (H):

meters

Efficiency (η):

decimal (0-1)

Pump Power (P):

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1. What is the Centrifugal Pump Power Equation?

The pump power equation calculates the required power to move a fluid through a system. It considers fluid density, flow rate, head, and pump efficiency to determine the mechanical power needed.

2. How Does the Calculator Work?

The calculator uses the pump power equation:

\[ P = \frac{\rho \times g \times Q \times H}{\eta} \]

Where:

\( P \) — Power (W)
\( \rho \) — Fluid density (kg/m³)
\( g \) — Gravity (9.81 m/s²)
\( Q \) — Flow rate (m³/s)
\( H \) — Head (m)
\( \eta \) — Pump efficiency (decimal 0-1)

Explanation: The equation calculates the hydraulic power divided by pump efficiency to determine required input power.

3. Importance of Pump Power Calculation

Details: Accurate power calculation is essential for proper pump selection, motor sizing, and energy efficiency assessments in fluid systems.

4. Using the Calculator

Tips: Enter fluid density (1000 kg/m³ for water), flow rate in m³/s, head in meters, and pump efficiency as a decimal (e.g., 0.8 for 80%). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is typical pump efficiency?
A: Centrifugal pumps typically range from 40-85% efficiency, with larger pumps generally more efficient.

Q2: How do I convert flow rate from L/s to m³/s?
A: Divide L/s by 1000 (1 m³/s = 1000 L/s).

Q3: What if my fluid isn't water?
A: Use the actual density of your fluid (e.g., 800 kg/m³ for diesel, 13600 kg/m³ for mercury).

Q4: How does head relate to pressure?
A: Head (m) = Pressure (Pa) / (density × gravity). 10 m head ≈ 1 bar pressure for water.

Q5: Should I add a safety factor?
A: In practice, engineers often add 10-20% safety margin to calculated power for system uncertainties.