1. What is the Pump Power Equation?

Definition: This calculator determines the hydraulic horsepower required by a pump based on flow rate, head, fluid density, and pump efficiency.

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

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( HP \) — Hydraulic horsepower
• \( Q \) — Flow rate (gallons per minute)
• \( H \) — Total head (feet)
• \( \rho \) — Fluid density (pounds per gallon)
• \( \eta \) — Pump efficiency (decimal)

Explanation: The formula calculates the power needed to move a specific volume of fluid against a certain head pressure, accounting for pump efficiency.

3. Importance of Pump Power Calculation

Details: Accurate power calculation ensures proper pump selection, energy efficiency, and system reliability.

4. Using the Calculator

Tips: Enter flow rate in GPM, head in feet, density in lb/gal (default 8.34 for water), and efficiency as decimal (default 0.85). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the constant 3960?
A: It's a conversion factor that combines various unit conversions to give horsepower directly.

Q2: What's a typical pump efficiency?
A: Most pumps operate between 50-85% efficiency, with centrifugal pumps typically around 70-85%.

Q3: How does density affect the calculation?
A: Denser fluids require more power to pump. Water is 8.34 lb/gal, while oils may range 6.5-7.5 lb/gal.

Q4: Does this include motor efficiency?
A: No, this calculates hydraulic horsepower. For brake horsepower, divide by motor efficiency.

Q5: What if I need kW instead of HP?
A: Multiply HP by 0.746 to convert to kilowatts.