1. What is the Flow Rate Formula?

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

Purpose: It helps engineers and technicians determine fluid flow rates in pipes, channels, and other conduits.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( V \) — Velocity (feet per second)
• \( A \) — Cross-sectional area (square feet)
• 448.83 — Conversion factor (1 ft³/s = 448.83 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 calculations are essential for designing piping systems, sizing pumps, and ensuring proper system operation.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: Why is the conversion factor 448.83?
A: This converts cubic feet per second to gallons per minute (1 ft³ = 7.48052 gallons, 60 seconds/minute → 7.48052 × 60 = 448.83).

Q2: How do I measure velocity in a pipe?
A: Use flow meters or calculate from pressure drop using Bernoulli's equation.

Q3: What's a typical velocity for water in pipes?
A: Typically 4-8 ft/s for water in supply lines, but varies by application.

Q4: How do I calculate cross-sectional area?
A: For circular pipes: A = π × (diameter/2)². For other shapes use appropriate area formulas.

Q5: Does this work for any fluid?
A: Yes, but the velocity should be appropriate for the specific fluid's viscosity and density.