💧 Pipe Flow Rate Calculator
Continuity equation Q = V × A for circular pipes
Enter any two of: Diameter, Velocity, Flow Rate
Results
Flow Rate
—
GPM
Velocity
—
ft/s
Pipe Area
—
in²
Mass Flow Rate
—
lb/min
Formula Reference
Q = V × A | A = πD²/4
Mass flow = Q × ρ
📝 Worked Example
Water flows through a 2-inch pipe at 5 ft/s. Find volumetric and mass flow rate.
| Input | Value |
|---|---|
| Diameter | 2 in |
| Velocity | 5 ft/s |
| Density (water) | 62.4 lb/ft³ |
A = π(2/12)²/4 = 0.02182 ft² | Q = 5 × 0.02182 = 0.1091 ft³/s = 49.0 GPM
Result: Q = 49.0 GPM | Mass flow = 183 lb/min