Presets
Playback
Pump, tank and weather
Pump flow follows speed, efficiency, valve opening and the square of the pipe diameter.
Events
Model checks
The science
What is modelled
Spring water and rain runoff collect in a source basin. A positive-displacement pump lifts it to an elevated tank; the village draws water from the tank by gravity. The tank level sets the service pressure; the pump motor heats and is cooled by a fan.
Equations
dVsource/dt = Qspring + Qrain - Qpump,dVtank/dt = Qpump - Qdelivered.- Rain capture
Q = R A / 3600(R in mm/h, A = 1800 m² gives L/s). - Pump
Q ≈ n d η v (D/100 mm)² (1 - clog), capped at 28 L/s. - Pressure
p ≈ 1 bar + 0.0981 (Hbase + Hwater) - friction. - Motor
C dT/dt = Ploss - k (T - Tamb), exact solution used in the page.
Checks run in the page
- Water conservation over 60 s: change of basin and tank plus delivery equals the inflow.
- The pump law against a hand calculation, including a 28 % clog.
- The closed-form motor temperature against fine Euler stepping.
Honest simplifications
Constant-area tanks, incompressible water, a fixed 14 m pump head, empirical pipe friction, no leaks and no water quality. It illustrates balancing flows and levels, not hydraulic design.
What to try
- Choose Thirsty village: the tank drains below the safe band and the pressure falls.
- Press Intake clog and compensate by raising the pump speed; watch the motor temperature.
- Choose Storm catchment and see the basin and tank approach their limits.