1. What is a Pump Flow Rate Calculator?

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

Purpose: It helps engineers and technicians determine the expected performance of pumps in fluid systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute, GPM)
• \( HP \) — Pump horsepower
• \( \eta \) — Pump efficiency (0-1)
• \( H \) — Total head (feet)
• \( \rho \) — Fluid density (pounds per gallon)

Explanation: The formula relates the pump's power input to its fluid output, accounting for system resistance (head) and fluid properties.

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 0.8), total head in feet, and fluid density (default 8.34 lb/gal for water). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the constant 3960 in the formula?
A: It's a conversion factor that relates horsepower, flow rate, head, and specific gravity in consistent units.

Q2: What's a typical pump efficiency value?
A: Centrifugal pumps typically range from 0.5-0.9 (50-90% efficient), with 0.8 being a common default.

Q3: How do I determine total head?
A: Total head is the sum of static head, friction losses, and pressure differences in the system.

Q4: What density should I use for other fluids?
A: For fluids other than water, use their specific weight divided by 7.4805 to get lb/gal (water = 8.34 lb/gal).

Q5: Can this be used for any pump type?
A: This formula works best for centrifugal pumps. Positive displacement pumps require different calculations.