1. What is Pump Flow Rate Calculation?

Definition: This calculator determines the flow rate of a pump based on its horsepower, efficiency, total head, and fluid density.

Purpose: It helps engineers and technicians size pumps and evaluate their performance in various hydraulic 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 to 1)
• \( H \) — Total head (feet)
• \( \rho \) — Fluid density (pounds per gallon)

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

3. Importance of Pump Flow Rate Calculation

Details: Accurate flow rate calculation ensures proper system design, energy efficiency, and prevents pump overload or underperformance.

4. Using the Calculator

Tips: Enter the pump horsepower, efficiency (default 0.85), 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, and head (1 HP = 3960 GPM·ft·lb/gal).

Q2: What's a typical pump efficiency value?
A: Centrifugal pumps typically range from 0.7 to 0.9 (70-90% efficient), while positive displacement pumps can be higher.

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

Q4: What density should I use for other fluids?
A: For different fluids, use their specific weight (e.g., 6.6 lb/gal for diesel, 7.5 lb/gal for gasoline).

Q5: Can this formula be used for all pump types?
A: This is primarily for centrifugal pumps. Positive displacement pumps require different calculations.