About this simulator
A steady-state pump network solver. Finds the operating point by intersecting the combined pump H‑Q
characteristic with the system resistance curve. Supports up to three pumps per group in two configurable
groups, covering single-pump, parallel, and series topologies. Mode 4 extends this with a
side-flow extraction node between the two groups, enabling modelling of networks where part of the
total flow is bled off before reaching the final outlet. All computation runs in the browser — no
backend or installation required.
System Curve
H_sys = H_z + (P_out−P_in)/(ρg) + H_loss(Q)
Static lift + pressure boundary + pipe friction. Friction calculated as K·Q² or from tabulated ΔH‑Q data.
Operating Point
H_pump(Q) − H_sys(Q) = 0
Root found by bisection (up to 100 iterations). Convergence guaranteed for well-defined monotone curves.
Parallel Pumps
Q_group(H_c) = Σ Q_i(H_c)
Common delivery head H_c; individual flows sum at that head. Group H‑Q inverted by bisection.
Series Groups
H_tot = H_A(Q) + H_B(Q) − H_mid(Q)
Same flow through both groups; heads add, mid-pipe friction subtracted.
Mode 4 — Side Flow
Q_tot = Q_main + Q_side
Continuity at split node A. Side flow from pipe model (Darcy‑Weisbach) or manual. Q_main continues to Group B.
Pump Affinity
H(Q,N) = (N/N_ref)² · H_ref(Q·N_ref/N)
Head and flow scale with speed ratio. N=0 gives zero head.
Hydraulic Power
P_hyd = ρ·g·Q·H
P_shaft = P_hyd / η
Delivered hydraulic power and estimated shaft power at specified efficiency.
Density Correction
H_sim = H_ref · (ρ_ref / ρ_sim)
Pump and system table heads rescaled to simulation fluid density. Flow values unaffected.
How to operate
1 Topology — select a configuration tab at the top:
Single pump · 1‑3 parallel (Group A) · Series A+B · Series with mid-pipe friction · Mode 4 side-flow network.
2 Pump curves — enter tabulated H[m] vs Q[m³/h] points in the left panel, or specify
analytic parameters (shut-off head, best-efficiency point, runout). Set fluid density and pump speed as needed.
3 System resistance — choose Method A (calculated friction: pipe diameter, length, K-factor)
or Method B (tabulated ΔH‑Q data). Set inlet and outlet pressures.
4 Run — click Run or enable Auto for continuous recalculation as parameters change.
5 Read results — operating flow, head, power, and node pressures appear in the right panel.
The centre plot shows H‑Q curves with the computed operating point marked.
