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Pipe Flow Calculator

Science & Engineering

Q=vA + sizing + velocity guide

Quick Answer

Pipe Flow Calculator: Q=vA + sizing + velocity guide. Pipe Flow Calculator uses standard science & engineering formulas to compute accurate results instantly.

Solve for flow Q
10.60 m³/h
Equivalent2.95 L/s
176.7 L/min

Calculation steps

  1. 1A = πd²/4 = π × (50.0 mm)² / 4 = 1963.5 mm²
  2. 2Q = v·A = 1.5 × 0.00196 = 10.60 m³/h

Recommended velocities

自来水给水1.0-2.0 m/s
消防给水≤ 2.5 m/s
重力排水0.7-1.5 m/s（自清流速 ≥0.6）
水泵吸水管1.0-1.2 m/s
压缩空气8-15 m/s
蒸汽20-40 m/s

Common DN inner diameters (steel pipe)

DN15 (1/2")内径 ~16 mm
DN20 (3/4")内径 ~21 mm
DN25 (1")内径 ~27 mm
DN50 (2")内径 ~53 mm
DN100 (4")内径 ~106 mm
DN200 (8")内径 ~207 mm
Flow continuity: Q = v·A always holds, but real sizing must also check pressure drop (Darcy-Weisbach) — Δp grows roughly with v² and shrinks with d⁵, so going one size up can halve pumping energy. Nominal DN is NOT the exact inner diameter: DN50 steel pipe is ~53 mm inside, while PPR "50" refers to the OUTER diameter (inner ~40 mm). Keep water below ~2 m/s to limit noise and water hammer; gravity drains need ≥0.6 m/s self-cleaning velocity.

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How to Use

  1. Enter known quantities: fill values and confirm units in the Pipe Flow Calculator.
  2. Instant solution: unknowns solve live with the formula shown transparently.
  3. Use constant/material tables: standard physical constants and material data are listed on this page.
  4. Compare conditions: change inputs to compare scenarios.

Key Points

  • Pipe Flow Calculator is a free online science & engineering tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: Q=vA + sizing + velocity guide.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Pipe Flow Calculator formula

Pipe Flow Calculator uses standard science & engineering formulas to compute accurate results instantly.

FAQ

How do I use the Pipe Flow Calculator?
Open the page and fill in the input fields — results update automatically. Q=vA + sizing + velocity guide.
Are the results accurate?
Yes. Standard formulas and conversion factors are used and verified.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required.
Does it work on mobile?
Yes. The responsive design works on phones, tablets and desktops.
Is my data saved?
No. Everything runs locally in your browser.

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Source & Updates

Based on CODATA recommended constants and standard physics formulas. Last updated: 2025-07

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Pipe Flow Calculator[EB/OL]. https://www.yijiansuan.com/en/c/science/pipe-flow

Results provided by this tool are for reference only and do not constitute professional advice.