1. What is the Flow Rate Formula for Pipe?

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

Purpose: It helps engineers, plumbers, and fluid system designers determine the flow capacity of piping systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( V \) — Velocity of fluid (feet per second)
• \( A \) — Cross-sectional area of pipe (square feet)
• 448.83 — Conversion factor (cubic feet to gallons and seconds to minutes)

Explanation: The velocity multiplied by area gives flow in cubic feet per second, which is then converted to gallons per minute.

3. Importance of Flow Rate Calculation

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

4. Using the Calculator

Tips: Enter the fluid 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: Why is the conversion factor 448.83?
A: It combines 7.48052 (gallons per cubic foot) and 60 (seconds per minute): 7.48052 × 60 = 448.83.

Q2: What's a typical velocity for water in pipes?
A: Residential systems: 4-8 ft/s, industrial systems: up to 10 ft/s, with lower velocities for viscous fluids.

Q3: How do I calculate pipe cross-sectional area?
A: For circular pipes: A = π × r² (r = radius in feet). For other shapes use appropriate area formulas.

Q4: Does this work for any fluid?
A: Yes, but the velocity should be appropriate for the specific fluid's viscosity and the system requirements.

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