Flow resistance of a compressed-air supply hose
Pressure drop along a compressed-air supply hose/line for a given flow rate, length and inner diameter — for sizing the air supply feeding an aerostatic bearing.
No login lock. Unit selectors for flow rate and both pressures reproduce the legacy dropdowns exactly (their option values are the code’s own unit indices/exponents, not relabeled). The reference nomogram above is the original, in Dutch (never redrawn, to avoid the risk of a transcription error in a numerical chart) — translated here for reference: "Leidinglengte, meter" = pipe length, m; "Inwendige diameter van de leiding, mm" = internal line diameter, mm; "Drukval in de leiding, bar" = pressure drop in the line, bar; "Werkdruk, bar (overdruk)" = working pressure, bar (gauge); "Luchtstroom, l/s (vrije lucht)" = air flow, l/s (free air). Caption: "Nomogram voor leidingberekeningen. Leidingdiameter 3,2-60 mm, luchtstroom 1-100 l/s" = nomogram for line-sizing; line diameter 3.2–60mm, air flow 1–100 l/s.
Method & references
- Empirical compressible-flow pressure-drop correlation for air in a supply hose/line: Δp ∝ Q^1.85 · L / d⁵ / p₁.
The computation is a literal port of the original client-side JavaScript from /calculators/pipeflow_air.htm. Results are verified equal to the original by an automated golden-master test. No formula has been re-derived or “improved”.