Fire Hydrant Flow Calculator

Hydrant Flow Equation:

\[ Flow = 29.7 \times d^2 \times \sqrt{P} \]

Hydrant Flow:

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1. What is the Fire Hydrant Flow Equation?

The fire hydrant flow equation estimates the water flow rate from a hydrant based on its diameter and the water pressure. This calculation is essential for firefighting operations and water system design.

2. How Does the Calculator Work?

The calculator uses the hydrant flow equation:

\[ Flow = 29.7 \times d^2 \times \sqrt{P} \]

Where:

\( d \) — Hydrant diameter (inches)
\( P \) — Water pressure (psi)
29.7 — Empirical coefficient

Explanation: The equation accounts for the relationship between hydrant diameter, water pressure, and resulting flow rate.

3. Importance of Hydrant Flow Calculation

Details: Accurate flow estimation is crucial for firefighting operations, ensuring adequate water supply, and designing water distribution systems.

4. Using the Calculator

Tips: Enter hydrant diameter in inches and pressure in psi. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the typical hydrant diameter?
A: Standard fire hydrants typically have diameters of 2.5 inches or 4.5 inches.

Q2: What pressure range is typical for hydrants?
A: Normal operating pressure ranges from 20 psi to 100 psi in most municipal systems.

Q3: Why is the coefficient 29.7?
A: This empirical coefficient accounts for friction loss and other hydraulic factors in the hydrant.

Q4: Are there limitations to this equation?
A: The equation assumes ideal conditions and may need adjustment for very large diameters or extreme pressures.

Q5: How accurate is this calculation?
A: It provides a good estimate but actual flow should be measured for critical applications.