1. What is the Water Hose Flow Rate Equation?

The water hose flow rate equation calculates the flow rate in gallons per minute (GPM) based on hose diameter and water pressure. This formula is commonly used in irrigation, firefighting, and plumbing applications to determine water flow capacity.

2. How Does the Calculator Work?

The calculator uses the water hose flow equation:

Where:

• \( GPM \) — Flow rate in gallons per minute
• \( D \) — Hose diameter in inches
• \( P \) — Water pressure in pounds per square inch (psi)

Explanation: The equation demonstrates that flow rate increases with the square of the diameter and the square root of pressure, showing how diameter has a greater impact on flow than pressure.

3. Importance of GPM Calculation

Details: Accurate flow rate calculation is essential for proper system design, ensuring adequate water supply for various applications, optimizing irrigation systems, and meeting fire protection requirements.

4. Using the Calculator

Tips: Enter hose diameter in inches and water pressure in psi. Both values must be positive numbers for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why is diameter squared in the equation?
A: The cross-sectional area of the hose increases with the square of the diameter, which directly affects the flow capacity.

Q2: What are typical GPM values for garden hoses?
A: Standard garden hoses (5/8 inch) typically flow 4-9 GPM at 40-60 psi, while larger hoses can flow significantly more.

Q3: Does hose length affect flow rate?
A: Yes, longer hoses create more friction loss, which reduces flow rate. This equation assumes minimal friction loss.

Q4: Are there limitations to this equation?
A: This is a simplified equation that doesn't account for friction loss, hose material, water temperature, or elevation changes.

Q5: Can this be used for fire hose calculations?
A: While the basic principle applies, fire hose calculations often require more complex formulas that account for friction loss and nozzle characteristics.