1. What is the Flow Rate Formula?

Definition: This calculator determines the volumetric flow rate in gallons per minute (GPM) based on fluid velocity and cross-sectional area.

Purpose: It's essential for hydraulic engineers, plumbers, and fluid system designers to size pipes and pumps correctly.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( V \) — Fluid velocity (feet per second)
• \( A \) — Cross-sectional area (square feet)
• 448.83 — Conversion factor (ft³/s to GPM)

Explanation: The formula converts the basic volumetric flow rate (V×A) from cubic feet per second to gallons per minute.

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculation ensures proper system design, prevents pipe erosion from excessive velocity, and maintains adequate pressure.

4. Using the Calculator

Tips: Enter the fluid velocity in ft/s and the cross-sectional area in ft². The calculator will output flow rate in GPM.

5. Frequently Asked Questions (FAQ)

Q1: Why is the conversion factor 448.83?
A: It converts cubic feet per second to gallons per minute (1 ft³/s = 448.83 GPM).

Q2: What's a typical velocity for water in pipes?
A: 2-5 ft/s for supply lines, 5-10 ft/s for drainage systems.

Q3: How do I calculate pipe cross-sectional area?
A: \( A = \pi \times r² \) where r is the pipe radius in feet.

Q4: Can I use this for gases?
A: Only for incompressible fluids. Gases require additional density factors.

Q5: What if my area is in square inches?
A: Convert to square feet first (divide by 144).