1. What is a Pipe Flow Calculator?

Definition: This calculator estimates the flow rate in gallons per minute (GPM) through a pipe based on flow velocity and cross-sectional area.

Purpose: It helps engineers, plumbers, and fluid system designers determine pipe flow rates for various applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The velocity and area are multiplied to get volumetric flow in ft³/s, then converted to GPM.

3. Importance of Pipe Flow Calculation

Details: Accurate flow rate calculation ensures proper pipe sizing, system efficiency, and prevents issues like excessive pressure drop or cavitation.

4. Using the Calculator

Tips: Enter the flow velocity in ft/s and pipe cross-sectional area in ft². For circular pipes, area = π × (diameter/2)².

5. Frequently Asked Questions (FAQ)

Q1: What's a typical flow velocity in pipes?
A: For water systems, 2-5 ft/s is common (lower for gravity systems, higher for pressurized).

Q2: How do I calculate pipe cross-sectional area?
A: For circular pipes: A = π × r² where r is radius in feet.

Q3: Why is the conversion factor 448.83?
A: It converts cubic feet per second (ft³/s) to gallons per minute (GPM).

Q4: Can I use this for other fluids besides water?
A: Yes, but the velocity recommendations may differ based on fluid viscosity.

Q5: What if I know diameter instead of area?
A: First calculate area using diameter: A = π × (diameter/2)², then use this calculator.