Home
Back
Water Flow Formula:
| From: | To: |
Water flow rate calculation determines the volume of water passing through a given cross-section per unit time. The formula Q = A × V × 60 calculates gallons per minute (gpm) based on cross-sectional area and velocity.
The calculator uses the water flow formula:
Where:
Explanation: This formula converts the basic flow equation (Q = A × V) from cubic feet per second to gallons per minute by multiplying by 60 seconds per minute and accounting for the conversion from cubic feet to gallons.
Details: Accurate flow rate calculation is essential for plumbing system design, irrigation planning, hydraulic engineering, pump selection, and water distribution system analysis.
Tips: Enter cross-sectional area in square feet and velocity in feet per second. Both values must be positive numbers. Common pipe areas can be calculated using π × (diameter/2)².
Q1: Why multiply by 60 in the formula?
A: The factor 60 converts the flow rate from cubic feet per second to cubic feet per minute, and the conversion from cubic feet to gallons is already accounted for in the units.
Q2: What are typical flow rates for residential plumbing?
A: Typical flow rates range from 2-8 gpm for showers, 1.5-3 gpm for faucets, and 3-7 gpm for toilet flush valves.
Q3: How do I measure velocity in a pipe?
A: Velocity can be measured using flow meters, calculated from pressure differentials, or estimated using timed volume collection methods.
Q4: Does pipe material affect flow rate?
A: Yes, pipe material affects friction loss, which can reduce velocity and thus flow rate. Smooth pipes like PVC have less friction than rough pipes like cast iron.
Q5: Can this formula be used for other fluids?
A: This specific formula is calibrated for water. For other fluids, density and viscosity differences would require adjustments to the conversion factors.