Calculation result
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Educational planning arithmetic only. Enter your own measured values and properties; these results are not an engineering specification, safety decision, or equipment recommendation.
Formula and method
For area and average velocity, Q = A × v. Circular pipe area A = πD²/4 using internal diameter. For a collected sample, Q = volume ÷ elapsed time. The result is volumetric flow, not mass flow. See OpenStax fluid dynamics for the continuity relationship.
Worked example
A pipe with 0.1 m internal diameter has an area of about 0.00785398 m². At 2 m/s average velocity, Q is about 0.015708 m³/s or 15.708 L/s.
Scope and limitations
The velocity must be the cross-sectional average; a point measurement is not automatically that average. Full-pipe flow is assumed in diameter mode. Pulsation, compression, leakage, partially filled pipe, and measurement error are outside this arithmetic model.
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