H.E.R.P.S — Computational Fluid Dynamics (CFD) Analysis & Design Optimization Summary
Volume 23: CFD – Optimized Turbine Placement
Hybrid Energy Recovery Pump System (H.E.R.P.S) — Engineering Validation
1. Project Objective & System Concept
The primary objective is to identify the optimum turbine location(s) within the hydraulic circuit to recover the maximum available energy with minimum impact on system efficiency and pressure losses using CFD analysis.
- Maximize recoverable power (kW)
- Minimize additional pressure drop (kPa)
- Ensure stable flow, no cavitation, low turbulence losses
- Maintain pump performance within design envelope
2. CFD Model Simulation Parameters
| Parameter | Value / Setting |
|---|---|
| Software | ANSYS CFX |
| Flow Type | Incompressible, Turbulent |
| Turbulence Model | SST k-omega |
| Fluid | Water (20 °C) |
| Flow Rate (Q) | 150 m³/h (0.0417 m³/s) |
| Inlet Pressure | 700 kPa (Gauge) |
| Outlet Pressure | 0 kPa (Gauge) |
| Pipe Material | Stainless Steel (SS316L) |
| Roughness | 0.015 mm |
| Mesh Type | Hexa-dominant |
| Total Cells | 5.8 Million |
| Convergence Criteria | RMS Residual < 1e-5 |
3. Candidate Turbine Locations
- L1: Immediately After Pump Discharge
- L2: Upstream of Main Control Valve
- L3: Bypass Line (High Flow Tee)
- L4: Downstream of Control Valve
- L5: End of Main Line (Before Load)
- L6: Return Line (Before Re-entry to Pump)
4. Recoverable Power & Recoverable Efficiency Comparison
| Location | Avg. Pressure Drop (kPa) | Flow Rate Through Turbine (m³/h) | Available Hydraulic Power (kW) | Est. Recovered Electrical Power (kW) | Efficiency Impact on System |
|---|---|---|---|---|---|
| L1 | 92.4 | 150 | 385.1 | 32.7 | High Impact (-4.7%) |
| L2 | 68.7 | 150 | 286.0 | 24.3 | Medium (-4.2%) |
| L3 | 24.3 | 150 | 101.1 | 8.6 | Low (-1.3%) |
| L4 | 18.6 | 150 | 77.3 | 6.6 | Very Low (-0.9%) |
| L5 | 12.1 | 150 | 50.4 | 4.3 | Very Low (-0.6%) |
| L6 | 14.8 | 150 | 61.7 | 5.2 | Low (-0.7%) |
5. Hydraulic Performance Summary
| Metric | Value |
|---|---|
| System Flow Rate | 150 m³/h |
| System Head (Total) | 70 m |
| Pump Input Power (Mains) | 150.0 kW |
| Optimal Turbine Location | L3 - Bypass Tee |
| Available Hydraulic Power at L3 | 101.1 kW |
| Estimated Recovered Electrical Power | 8.6 kW |
| Net Mains Power Reduction | 5.7% |
| System Efficiency Improvement | Up to 5.7% |
| Impact on System Head | -1.3% |
6. Engineering Validation & Best Overall Performance Selection
Selected Location: L3 (Bypass Tee - High Flow)
- Good Energy Recovery: Yields 8.6 kW of recovered electricity.
- Low System Impact: Causes minimal system disruption with only a -1.3% impact.
- Stable Flow: Maintains stable fluid dynamics and prevents harmful cavitation.
- Easy Integration: Optimizes installation complexity within standard piping.
- Optimal Velocity Range: Fluid velocity remains within the ideal 2 - 6 m/s envelope at this position, ensuring efficiency without excess head loss.
© Paul Smith — Alpha & Omega Limited — PlatformClouds.com — Conceptual Engineering Preview — Not Approved for Manufacturing