A centrifugal booster cutaway with a variable-frequency drive feeds an elevated, pressure-dependent demand branch, and a remote pressure sensor reports back. Adjust suction pressure, target pressure, elevation, demand, speed mode and power availability, and watch impeller speed, delivered flow, pump head and estimated shaft power respond.
• A real-time 3D view with numbered, clickable parts: centrifugal booster cutaway; variable-frequency drive; remote pressure sensor; elevated demand branch; pump and system relationship. Scene tools include home view, focus-selected-part, auto-rotate, expand and show/hide labels, and drag-to-orbit with pinch-to-zoom. • Experiment controls: pump suction pressure (50–350 kPa); remote pressure target (200–500 kPa); elevation to controlled outlet (0–30 m); demand at target pressure (5–35 L/min); automatic speed command; manual speed fraction (0.1–1); pump power available, plus a show flow/process markers toggle, pause/resume, single-step buttons (0.1 s and 1 s), a playback-speed selector and a restart experiment action. • Live readouts: remote outlet pressure; delivered flow; actual speed; pump differential head; target minus outlet pressure; estimated shaft input. A model response curve is drawn beside the 3D view and updates as you change controls. • A Curves & measurements tab with two live charts, the model equations as written in the simulator and snapshot readouts; an Experiments tab with 3 guided presets (overload the available head; pump outage; manual speed comparison) plus a model-verification bench, timestamped event log and copyable trial report. • A Learn & assess tab with 3 lessons (follow the system; connect the measurements; interpret the model), a 2-question knowledge check with reset, and a written model-scope statement.
The generic pump curve is Hp = 45 s² − 0.02 Q², so head scales with the square of speed fraction s. Outlet pressure is suction pressure plus 9.80665 times (pump head minus elevation), less a branch loss, and demand flow depends on how close outlet pressure is to the target. In automatic mode the model raises speed to bring outlet pressure to target.
The response-curve panel plots the pump head curve against the required system head so you can see why raising the elevation or lowering suction pressure demands more speed.
If required head exceeds what the pump can produce at 100% speed, speed saturates and the target pressure is not met. With power removed, source head alone cannot reach the outlet and delivery stops. In manual mode, pump head at shutoff falls roughly with speed squared.
The automatic command is a feedforward calculation from the model, not a tuned commercial PID. There is no cavitation, minimum-flow, efficiency-map or detailed VFD electrical model, and shaft input power uses an assumed 0.65 efficiency. It is a generic educational model, not a sizing tool.
Holding pressure at the far end of the system compensates for demand-dependent losses. The remote sensor tells the drive how much speed is actually needed.
Speed saturates and the pressure target is no longer met. The Target minus outlet pressure value shows the shortfall.
Head varies approximately with the square of speed, so a small speed reduction cuts head noticeably. The manual-speed experiment demonstrates this at shutoff.
No. It uses a specified generic pump curve and ideal hydraulics. A real design must use manufacturer curves, code requirements and proper controls tuning.