Calculator Inputs
Example Data Table
Use this sample dataset to validate the calculator or explain a lab demonstration.
| Case | Target | Density (kg/m³) | Flow Rate (m³/s) | Diameter (mm) | Angle (deg) | Velocity Factor | Expected Trend |
|---|---|---|---|---|---|---|---|
| 1 | Flat plate | 1000 | 0.010 | 40 | 90 | 0.00 | Mainly axial force |
| 2 | Curved vane | 1000 | 0.020 | 50 | 135 | 0.85 | Higher resultant force |
| 3 | Hemispherical cup | 998 | 0.018 | 45 | 180 | 0.90 | Highest axial reversal |
| 4 | Curved vane | 850 | 0.012 | 35 | 120 | 0.80 | Lower force from density |
Formula Used
Jet area: A = pi × d² / 4
Jet velocity from continuity: V = Q / A
Mass flow rate: ṁ = rho × Q × n
Outlet velocity: V₂ = k × V
Axial force: Fx = C × ṁ × (V - V₂ cos theta)
Lateral force: Fy = C × ṁ × (0 - V₂ sin theta)
Resultant force: FR = sqrt(Fx2 + Fy2)
Jet power: P = 0.5 × ṁ × V²
These equations come from linear momentum balance for a control volume around the jet and target surface. The impact coefficient adjusts ideal results for losses or experimental bias.
How to Use This Calculator
- Choose the target shape that best matches the surface.
- Enter fluid density, flow rate, and nozzle diameter.
- Leave jet velocity blank to derive it automatically.
- Set the deflection angle or let the target type fix it.
- Enter outlet velocity factor for surface losses.
- Use impact coefficient to reflect measured correction.
- Submit the form and review forces above the form.
- Download a CSV summary or print the page as PDF.
Frequently Asked Questions
1. What does jet impact force represent?
It is the force created when a moving fluid jet changes momentum after striking a plate, vane, or cup.
2. Why does the calculator ask for outlet velocity factor?
Real surfaces create friction and splash losses. The factor reduces outlet speed so results better match practical equipment behavior.
3. When should I leave jet velocity blank?
Leave it blank when flow rate and nozzle diameter are known. The calculator then derives velocity from continuity automatically.
4. Why is a hemispherical cup force usually higher?
It reverses the jet direction more strongly than a flat plate. Greater momentum change produces a larger axial reaction force.
5. What is the impact coefficient used for?
It adjusts the theoretical force for nonideal conditions, including turbulence, imperfect alignment, measurement uncertainty, and structural effects.
6. Can this calculator support multiple jets?
Yes. Enter the number of equal jets. The model scales mass flow and force using that multiplier.
7. Is this suitable for turbine teaching labs?
Yes. It is useful for fluid mechanics demonstrations, Pelton wheel concepts, control volume exercises, and momentum validation checks.