Model flow split using geometry and operating inputs. Review results, percentages, imbalance, and exportable records. Designed for quick engineering checks and comparative impeller studies.
| Case | Density (kg/m³) | Diameter (m) | Width (m) | Speed (rpm) | Flow Coefficient | Slip | Blockage | Blades | Effective Mass Flow (kg/s) | Non Uniformity (%) |
|---|---|---|---|---|---|---|---|---|---|---|
| Reference Example | 1.225 | 0.420 | 0.050 | 2950 | 0.160 | 0.920 | 0.080 | 12 | 0.710020 | 14.821205 |
| Balanced Weighting | 1.225 | 0.420 | 0.050 | 2950 | 0.160 | 0.920 | 0.080 | 12 | 0.710020 | 11.785113 |
| Tip Biased Estimate | 1.225 | 0.420 | 0.050 | 2950 | 0.160 | 0.920 | 0.080 | 12 | 0.710020 | 21.752705 |
This calculator applies a weighted outlet flow model. It estimates total impeller discharge first. It then redistributes that flow across hub, mid, and tip zones using user supplied weighting factors.
1) Tip speed
U2 = π × D2 × N / 60
2) Radial outlet velocity
Vr2 = φ × U2
3) Outlet area
A2 = π × D2 × b2
4) Ideal mass flow
ṁideal = ρ × A2 × Vr2
5) Effective mass flow
ṁ = ṁideal × σ × (1 − kb)
6) Zone weighting
Whub = 0.30 × whub
Wmid = 0.40 × wmid
Wtip = 0.30 × wtip
7) Zone flow share
fi = Wi / ΣW
8) Zone mass flow
ṁi = fi × ṁ
9) Local zone velocity
Vi = ṁi / (ρ × Ai)
10) Non uniformity index
Index = standard deviation of zone mass flows ÷ mean zone mass flow × 100
Impeller mass flow distribution affects efficiency, pressure rise, recirculation, and blade loading. Engineers often need a quick estimate before detailed CFD work. This calculator supports that early assessment stage with structured inputs and clear zone based outputs.
The model uses outlet diameter, width, speed, and flow coefficient to estimate radial discharge. Slip factor reduces the ideal discharge to reflect real blade exit behavior. Blockage factor then removes part of the flow area to account for thickness, wake, and practical passage restriction.
Many impellers do not pass flow uniformly from hub to tip. Manufacturing limits, blade angle changes, clearance effects, and inlet distortion can all skew the final distribution. That is why the calculator includes independent hub, mid, and tip weights. These weights help represent likely loading patterns without requiring a full three dimensional solver.
The non uniformity index is useful when comparing alternative geometries. Lower values usually indicate a flatter outlet profile. Higher values suggest stronger flow migration, local overloading, or possible separation risk. The hub to tip bias value also helps identify whether the estimate favors inner radius discharge or outer radius discharge.
Use this tool for preliminary engineering studies, concept comparisons, and report preparation. It is best suited to screening work and parametric checks. Final design decisions should still include test data, validated correlations, or high fidelity flow simulation.
It estimates total impeller mass flow and distributes that flow across hub, mid, and tip outlet zones using a weighted engineering model.
No. It is a fast preliminary tool. It helps with screening, comparison, and reporting, but detailed design still needs validation through experiments or higher fidelity simulation.
Slip factor reduces ideal blade exit performance. Real impellers rarely transfer momentum perfectly, so slip helps correct the mass flow estimate toward more realistic values.
It represents effective area loss caused by blade thickness, wakes, leakage effects, or local passage restriction. A higher blockage factor lowers effective discharge.
Use values near 1.00 for balanced flow. Increase a zone weight when you expect stronger discharge there. Decrease it when you expect weaker passage loading.
It measures how uneven the zone mass flows are. Lower values indicate a flatter distribution. Higher values indicate stronger skew and greater outlet imbalance.
Yes. Enter the correct fluid density and relevant operating values. The equations are general, but interpretation should match the machine and fluid regime.
It provides a quick passage level reference. This helps compare designs with different blade counts and supports early load balancing checks.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.