1. What is the Expected Flow from a Well Pump?

Definition: This calculator estimates the flow rate (in gallons per minute) that a well pump can deliver based on its horsepower, efficiency, and the total dynamic head.

Purpose: It helps well drillers, pump installers, and property owners determine the expected water delivery rate from a pumping system.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( HP \) — Pump horsepower
• \( \eta \) — Pump efficiency (dimensionless, 0-1)
• \( H \) — Total dynamic head (feet)

Explanation: The formula converts mechanical power to hydraulic power, accounting for pump efficiency and the work needed to lift water against the total head.

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 the pump horsepower, efficiency (default 0.8 for 80% efficiency), and total dynamic head in feet. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is total dynamic head?
A: It's the total equivalent height the pump must overcome, including vertical lift, pipe friction, and pressure requirements.

Q2: What's a typical pump efficiency?
A: Most submersible pumps operate at 70-85% efficiency (0.7-0.85). Surface pumps may be slightly less efficient.

Q3: What flow rates are typical for residential wells?
A: Most homes need 5-20 GPM, with higher flows required for irrigation or multiple households.

Q4: How do I find my pump's horsepower?
A: Check the pump nameplate or manufacturer specifications. Common residential pumps are 1/2 HP to 1-1/2 HP.

Q5: Does this account for pipe size limitations?
A: No, this is theoretical maximum. Actual flow may be limited by pipe diameter and friction losses.