1. What is Pipe Flow Rate?

Definition: This calculator determines the volumetric flow rate of liquid through a pipe in gallons per minute (GPM).

Purpose: It helps engineers, plumbers, and technicians design and analyze fluid systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute, GPM)
• \( V \) — Flow velocity (feet per second, ft/s)
• \( A \) — Cross-sectional area (square feet, ft²)
• 448.83 — Conversion factor (cubic feet to gallons and seconds to minutes)

Explanation: The flow velocity multiplied by pipe area gives volumetric flow, which is then converted to GPM.

3. Importance of Flow Rate Calculation

Details: Proper flow rate estimation ensures adequate system performance, prevents pipe damage, and helps in pump selection.

4. Using the Calculator

Tips: Enter the flow velocity in ft/s and pipe cross-sectional area in ft². All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I find pipe cross-sectional area?
A: For circular pipes: \( A = \pi \times (D/2)^2 \) where D is diameter in feet.

Q2: What's a typical flow velocity?
A: For water, 2-5 ft/s is common in plumbing systems to avoid noise and erosion.

Q3: Why the 448.83 conversion factor?
A: It converts ft³/s to GPM (1 ft³ = 7.48052 gallons, 1 minute = 60 seconds).

Q4: Does this work for any liquid?
A: Yes, but the formula assumes incompressible flow (valid for most liquids).

Q5: How does pipe material affect flow rate?
A: Material affects friction loss but not this basic calculation. Use more advanced formulas for long pipes.