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Water Flow Calculation Formula

Water Flow Formula:

\[ Q = V \times A \times 448.83 \]

ft/s
ft²
GPM

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1. What is the Water Flow Calculation Formula?

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

Purpose: It helps engineers, plumbers, and irrigation specialists determine water flow rates in pipes and channels.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q = V \times A \times 448.83 \]

Where:

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

3. Importance of Water Flow Calculation

Details: Accurate flow calculations ensure proper pipe sizing, pump selection, and system efficiency in plumbing and irrigation systems.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What's a typical water velocity in pipes?
A: Domestic plumbing typically uses 4-8 ft/s, while irrigation systems may use 2-5 ft/s.

Q2: How do I calculate pipe cross-sectional area?
A: For circular pipes, use \( A = \pi \times r^2 \) where r is the radius in feet.

Q3: Why is the conversion factor 448.83?
A: It combines 7.48052 (gallons per cubic foot) and 60 (seconds per minute).

Q4: Can this be used for other liquids?
A: Yes, but the density may affect actual flow rates in some cases.

Q5: What's the maximum flow rate this can calculate?
A: There's no theoretical maximum, but practical pipe systems rarely exceed 20 ft/s velocity.

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