https://pipeflowlab.com Free pipe pressure-drop, head-loss, and pump-sizing calculators with a built-in fitting counter, temperature-adjusted viscosity, and energy-cost estimator. en-us Sun, 28 Jun 2026 00:00:00 GMT https://pipeflowlab.com/guides/pump-affinity-laws https://pipeflowlab.com/guides/pump-affinity-laws Sun, 28 Jun 2026 00:00:00 GMT How centrifugal pump speed and impeller diameter change flow, head, and power — the three affinity laws with worked examples and VFD savings calculations. https://pipeflowlab.com/guides/reynolds-number https://pipeflowlab.com/guides/reynolds-number Thu, 04 Jun 2026 00:00:00 GMT The Reynolds number predicts laminar vs turbulent pipe flow: Re = ρvD/μ, the 2,000–4,000 transition, the friction-factor link, and worked examples. https://pipeflowlab.com/guides/npsh-cavitation https://pipeflowlab.com/guides/npsh-cavitation Thu, 04 Jun 2026 00:00:00 GMT NPSH explained: NPSHa vs NPSHr, the cavitation mechanism, the vapor-pressure penalty, margin per HI 9.6.1, and how to stop pump cavitation. https://pipeflowlab.com/guides/water-hammer https://pipeflowlab.com/guides/water-hammer Tue, 26 May 2026 00:00:00 GMT Water hammer is a transient pressure spike from sudden valve closure. The Joukowsky equation, critical closure time, column separation, and proven fixes. https://pipeflowlab.com/guides/hazen-vs-darcy https://pipeflowlab.com/guides/hazen-vs-darcy Wed, 06 May 2026 00:00:00 GMT Hazen-Williams is empirical, water-only, closed-form. Darcy-Weisbach is physically grounded, fluid-agnostic, and iterative. Here's how to pick the right one. https://pipeflowlab.com/guides/equivalent-length-101 https://pipeflowlab.com/guides/equivalent-length-101 Wed, 06 May 2026 00:00:00 GMT A 90° elbow acts like 30 diameters of straight pipe; a globe valve like 340. Where these numbers come from, what they cost, and why calculators ignore them. https://pipeflowlab.com/guides/pipe-material-cfactors https://pipeflowlab.com/guides/pipe-material-cfactors Wed, 06 May 2026 00:00:00 GMT Hazen-Williams C and Darcy roughness ε for every common pipe material, with new and aged values, sources, and notes on how each ages in service. https://pipeflowlab.com/guides/pump-curves-explained https://pipeflowlab.com/guides/pump-curves-explained Wed, 06 May 2026 00:00:00 GMT Pumps don't deliver a fixed flow. They deliver where their own head-vs-flow curve crosses the system's resistance curve. This guide walks through the visual.