1. What is a Well Water Flow Rate Calculator?

Definition: This calculator estimates the water flow rate from a well pump system based on pump horsepower, efficiency, and total dynamic head.

Purpose: It helps well owners, water system designers, and maintenance professionals determine the expected water delivery rate of a pump system.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Water flow rate (gallons per minute)
• \( HP \) — Pump horsepower
• \( \eta \) — Pump efficiency (decimal between 0 and 1)
• \( H \) — Total dynamic head (feet)
• 3960 — Conversion constant (ft-lb/min per HP)
• 8.34 — Weight of water (lb/gal)

Explanation: The formula converts pump power into water flow by accounting for the energy required to lift water against gravity and system resistance.

3. Importance of Flow Rate Calculation

Details: Proper flow rate estimation ensures adequate water supply, correct pump sizing, and efficient system operation.

4. Using the Calculator

Tips: Enter pump horsepower (HP), efficiency (default 0.85 for 85% efficient pumps), and total dynamic head in feet. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is total dynamic head (H)?
A: It's the vertical distance from water level to discharge point plus friction losses in pipes, measured in feet.

Q2: What's a typical pump efficiency value?
A: Most submersible pumps are 70-85% efficient (0.7-0.85), while jet pumps are typically 50-60% efficient.

Q3: Why 3960 in the formula?
A: This constant converts horsepower (550 ft-lb/sec) to ft-lb/min (550 × 60 = 33,000) and divides by 8.33 lb/gal water.

Q4: How accurate is this calculation?
A: It provides theoretical maximum flow. Actual flow may be lower due to system restrictions or higher specific gravity.

Q5: What if my pump is rated in kW instead of HP?
A: Convert kW to HP by multiplying by 1.341 (1 kW = 1.341 HP).