This simulator models a sectional end-suction centrifugal pump — impeller, volute casing, wear ring, mechanical seal, shaft/bearings and coupled motor — using a synthetic quadratic pump curve intersected with a quadratic system-resistance curve. Energize the motor, prime the casing, change speed, static lift, system resistance and liquid density, and watch flow, head and power settle to the new operating point.
• A real-time 3D cutaway workbench with home view, focus-selected-part, show full enclosure, exploded view, auto-rotate, expand and hide-labels scene tools, plus click-to-inspect numbered components (volute casing/discharge throat, backward-curved impeller and eye, axial suction flange and wear ring, mechanical seal and gland, shaft/bearings/coupling, finned motor, tangential discharge and flow path, and a speed/head/power recorder). • Experiment controls: motor speed demand (600–2,400 rpm), motor energized and casing primed checkboxes, discharge fully closed checkbox, static system lift (0–35 m), system resistance coefficient and liquid density sliders, pause/resume, single-step (0.1 s) and 1 s-step buttons, and four playback speeds (10× slow motion, real time, 10× faster, 1 minute per second). • A Curves & measurements analysis tab with two live charts (delivery flow; hydraulic vs. shaft power), the underlying pump/system equations and impeller tip-speed formula, and snapshot measurement readouts (shaft speed, flow, head, tip speed, efficiency, hydraulic and shaft power, shutoff head). • An Experiments tab with four guided fixtures (normal delivery, unprimed casing, closed discharge, low speed against lift) and a Model verification bench that runs independent deterministic checks without disturbing the live trial, plus a timestamped event log and copyable trial report. • A Learn & assess tab with four guided lessons, a knowledge-check quiz with reset, and a written model-scope statement linking to a pump affinity-laws reference.
A primed, rotating impeller accelerates liquid outward from its central eye through curved passages, converting shaft work into kinetic and pressure energy. The volute casing then collects that flow around the impeller's perimeter and guides it toward the tangential discharge, contributing further velocity-to-pressure conversion.
The simulator solves for the operating point where the pump's head-versus-flow curve, Hpump(Q) = 40(n/1800)² − 0.006Q², intersects the system curve Hsystem(Q) = Hstatic + K·Q². Because available head scales with the square of the speed ratio (the pump affinity law), halving speed cuts shutoff head to a quarter — enough, in the low-speed experiment, for a modeled nonreturn valve to block delivery entirely when static lift exceeds the reduced shutoff head.
A closed discharge does not stop the impeller from developing head — it stops delivery. With the model's blocked-discharge state, flow drops to zero while head approaches the theoretical shutoff value near 40 m, and hydraulic power (which requires both flow and head) falls to zero even though the motor still draws an illustrative no-flow shaft loss of 0.3(n/1800)³ kW.
This is a synthetic quadratic pump/system model with quasi-steady incompressible flow, a first-order 0.8 s motor speed response and a representative (not manufacturer-certified) impeller geometry. It does not model water hammer, real efficiency mapping, dry-running heat damage or wear-ring leakage — the unprimed state is an explicit no-delivery teaching condition, not a thermal or mechanical failure simulation.
At the central eye, on the impeller's rotational axis. From there it moves outward through curved rotating passages toward the perimeter, where the volute casing collects it and directs it to the discharge — this is the entry path modeled in the simulator's cutaway workbench.
Yes — a primed, rotating pump with a fully closed discharge can still develop "shutoff head" (the maximum head on its curve), even though no useful hydraulic power is delivered since hydraulic power requires both flow and head. The simulator's closed-discharge experiment demonstrates exactly this.
Pump head scales with the square of the speed ratio under the pump affinity laws, so cutting speed in half cuts available shutoff head to one quarter. If that reduced shutoff head falls below the static lift the system requires, the modeled nonreturn valve prevents delivery altogether — shown in the low-speed experiment.
No. It uses a synthetic quadratic pump curve and system-resistance model with representative, non-CAD geometry for teaching purposes. Real pump selection requires the manufacturer's tested performance curve, NPSH data and a site-specific system analysis.