Terraced canal · lift station 04
The long climb
to the upper basin
to the upper basin
Balance head, flow and storage before the evening dispatch.
Preparing the station…
Intake obstruction · decision
The filter is catching debris.
Flow has dropped. A brief clean-out costs pumping time; running through keeps the delivery moving but leaves the intake restricted.
Speed
Station ready. Set the pump and sluice, then start the dispatch clock.00:00 / 03:00
Operating plan
Choose a starting strategy
Plant controls
10 adjustable variables · SI units
Live telemetry
Fixed-step solver · 120 Hz
Upper level
4.25m
target 4.8–6.4 m
Source level
2.75m
lower basin
Pump flow
0L/s
solved operating point
Outlet flow
0L/s
gate + demand
Input power
0kW
hydraulic / η
Energy used
0.00kWh
target under 1.05
Water delivered
0.0m³
dispatch total
Pump head
0.0m
static + pipe loss
System traces
Last 60 simulated seconds
Upper basin level
LiveAnalytic projection
Volumetric flow rate
PumpOutflow
The science · equations & assumptions
1 · Pump operating point
Hₚ(Q) = H₀ n² [1 − (Q / (Q₀ n))²]
Hₚ = Hstatic + (f L / D + K) v² / (2g), v = Q / Apipe
The solver finds the intersection by bounded bisection (36 iterations). The inlet valve and intake filter limit the available free-delivery flow.
2 · Gravity gate & reservoir balance
Qgate = Cd Aopening √(2 g max(h − htail, 0))
dhupper/dt = (Qpump + Qrain − Qgate − Qdemand − Qloss) / Aupper
dhlower/dt = −Qpump / Alower
3 · Power and energy
Pinput = ρ g Qpump Htotal / η
ΔE [kWh] = P [W] · Δt [s] / 3,600,000
Assumptions & honest simplifications
- Water is treated as incompressible with constant density; flow is quasi-steady inside the pipe.
- The pump curve is an idealised quadratic curve; cavitation, motor start-up and detailed pump maps are omitted.
- Darcy–Weisbach friction uses a fixed friction factor plus a lumped minor-loss coefficient; Reynolds-dependent friction is not solved.
- Gate discharge uses an approximate free-orifice equation; submergence, approach velocity and transient wave propagation are simplified.
- Rainfall is converted to a uniform catchment inflow. Wind loss is a small illustrative evaporation term, not a weather forecast.
- The two basins are well-mixed level stores. The geometry is artistic and is not a surveyed civil-engineering model.
Units: m, s, m², m³/s, W, kWh. Gravity g = 9.80665 m/s²; water density ρ = 998.2 kg/m³. Approximate model: suitable for learning and experimentation, not infrastructure design.
Hint: compare the pump curve with the basin balance. Opening the sluice too far can undo the lift.