1. What is a Pump Flow Rate Calculator?

Definition: This calculator estimates the flow rate of a pump in gallons per minute (GPM) based on horsepower, efficiency, and head.

Purpose: It helps engineers and technicians determine the expected flow rate of pumps in various applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula relates the power input (HP), pump efficiency, and the height the fluid must be lifted (head) to determine the flow rate.

3. Importance of Pump Flow Rate Calculation

Details: Accurate flow rate estimation ensures proper pump selection, system design, and energy efficiency in fluid transport systems.

4. Using the Calculator

Tips: Enter the pump horsepower, efficiency (default 0.85), and total head in feet. All values must be > 0, with efficiency between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is the constant 3960 in the formula?
A: This is the conversion factor that relates horsepower, flow rate, and head (1 HP = 3960 GPM·ft).

Q2: What's a typical pump efficiency value?
A: Most pumps operate between 70-90% efficiency (0.7-0.9), with centrifugal pumps typically around 85%.

Q3: How is total dynamic head determined?
A: It's the sum of static head (vertical distance) and friction head (pipe resistance).

Q4: Does this work for all pump types?
A: This formula is most accurate for centrifugal pumps; positive displacement pumps may require different calculations.

Q5: What if my efficiency is given as percentage?
A: Divide the percentage by 100 (e.g., 85% efficiency = 0.85 in the calculator).