This simulator isolates local fitting losses from background pipe friction in a horizontal two-elbow rack with a rising-stem valve and a removable-basket strainer. Adjust flow, bore, pipe length, roughness, elbow loss coefficient, valve travel and strainer fouling to see how each fitting's loss coefficient adds to the total head loss.
• A real-time 3D cutaway workbench of the rack inlet, two 90° elbows, a rising-stem valve with visible stem/plug travel, a Y-strainer with a removable mesh basket, a fitting pressure-tap network, a component-loss ledger and a discharge/measurement console, with home view, focus-selected-part, full-enclosure toggle, exploded view, auto-rotate, expand and show/hide labels controls. • Nine laboratory controls: imposed volume flow (0–5 L/s), internal pipe bore (20–100 mm), straight-pipe length (1–80 m), equivalent wall roughness ε (0–1 mm), dynamic viscosity (0.5–20 mPa·s), inlet gauge pressure (50–400 kPa), K per 90° elbow (0.2–2, two installed), valve travel (10–100%) and strainer loss coefficient (0.5–15). • Playback controls: pause/resume, 0.1 s and 1 s step advances, four speeds, plus 'Open valve fully' and 'Clean strainer' quick actions. • A Curves & measurements tab with a pressure-vs-path-distance chart (grouped fitting jumps), a pipe/fitting/total-loss history chart, the full equation set (Darcy–Weisbach, teaching valve-K law, equivalent length) and snapshot readouts. • An Experiments tab with four guided fixtures (nominal fitting rack, throttle the valve, fouled strainer, long piping dominates) and a Model verification bench with an independent-check run, timestamped event log and copyable trial report. • A Learn & assess tab with guided lessons, a knowledge-check quiz with reset, and a written model-scope statement with a reference link.
Minor losses are local, irreversible head losses at fittings — elbows, valves, strainers and other geometry changes — each characterized by a loss coefficient K applied to the velocity head: h = K·V²/(2g). The name refers to their localized nature, not their magnitude: the simulator's throttle-valve experiment uses the teaching law Kvalve = 0.15 + 2(1/o² − 1), where o is fractional valve travel, so a valve closed to 25% travel can contribute more loss than the entire straight-pipe run.
Because every fitting here shares the same reference bore, the simulator can sum all local losses (2×Kelbow + Kvalve + Kstrainer) against one common velocity head, then add the distributed pipe friction loss for the total.
The equivalent-length metric, Lequivalent = ΣK·D/f, expresses total fitting loss as an equal-loss length of straight pipe at the current Darcy friction factor — it recalculates whenever f changes, so it is not a fixed geometric length. Comparing the 'Long piping dominates' and 'Throttle the valve' experiments shows how the balance between distributed and local loss shifts with pipe length versus fitting restriction.
Constant fitting K values are illustrative turbulent-flow estimates, not validated low-Reynolds-number correlations — below Re = 4000 the model flags local-loss outputs as exploratory only. No clogging dynamics, entrance effects or cavitation are modeled, and the chart's fitting-loss placement at 25/50/75% of path distance is for display clarity, not a resolved near-field pressure distribution.
Minor losses are localized head losses caused by fittings such as elbows, valves and strainers, each modeled with a loss coefficient K applied to the velocity head: h = K·V²/(2g). "Minor" refers to their local nature, not necessarily a small magnitude — a throttled valve can dominate total loss.
The simulator's teaching law Kvalve = 0.15 + 2(1/o² − 1) increases the valve coefficient sharply as travel o decreases. In the "Throttle the valve" experiment, closing to 25% travel makes valve loss dominate the total head loss.
Equivalent length, Lequivalent = ΣK·D/f, converts the sum of fitting loss coefficients into an equal-loss length of straight pipe. It changes whenever the Darcy friction factor f changes, so it is a condition-dependent reference, not a fixed geometric value.
No. The constant K values are illustrative turbulent-flow estimates. Below a Reynolds number of 4000, the simulator explicitly flags local-loss outputs as exploratory only, since real fitting coefficients become flow-dependent at low Reynolds numbers.