1. What is the Pump Power Equation?

The pump power equation calculates the required horsepower for a pump based on flow rate, total head, specific gravity of the fluid, and pump efficiency. It's essential for proper borehole pump selection and sizing.

2. How Does the Calculator Work?

The calculator uses the pump power equation:

Where:

• \( Q \) — Flow rate in gallons per minute (GPM)
• \( H \) — Total dynamic head in feet (ft)
• \( SG \) — Specific gravity of the fluid (1.0 for water)
• \( \eta \) — Pump efficiency as a decimal (0-1)
• 3960 — Conversion factor to horsepower

Explanation: The equation calculates the theoretical power required to move a fluid at a given flow rate against a specific head, adjusted for fluid density and pump efficiency.

3. Importance of Proper Pump Sizing

Details: Correct pump sizing ensures efficient operation, prevents energy waste, reduces wear and tear, and ensures adequate water delivery. Undersized pumps can't meet demand, while oversized pumps waste energy and may cause system damage.

4. Using the Calculator

Tips:

• Measure flow rate accurately (GPM)
• Calculate total dynamic head including vertical lift and friction losses
• Use specific gravity of 1.0 for water
• Typical pump efficiency ranges from 0.5 to 0.85 (50%-85%)

5. Frequently Asked Questions (FAQ)

Q1: What is total dynamic head?
A: The total height the pump must move the fluid, including vertical lift and friction losses in pipes and fittings.

Q2: How do I determine pump efficiency?
A: Manufacturer specifications typically provide this. For estimation, use 0.7-0.85 for submersible pumps, 0.5-0.7 for smaller pumps.

Q3: Should I add a safety factor?
A: Yes, typically add 10-20% to the calculated HP to account for system variations and future needs.

Q4: What's the difference between BHP and WHP?
A: Brake horsepower (BHP) is power at the pump shaft, while water horsepower (WHP) is the actual hydraulic power delivered to the fluid.

Q5: How does viscosity affect the calculation?
A: High viscosity fluids require more power. For fluids significantly thicker than water, consult pump performance curves.