VORTEX CONTROL & DRAFT TUBE DYNAMICS
THE PHYSICS OF VORTEX FORMATION
At 40-60% load, water exits the runner with residual swirl, creating a helical vortex rope. If the vortex frequency matches structural resonance, damage accumulates rapidly.
FREQUENCY CALCULATION
- Runner Speed: 600 RPM
- Runner Freq: 10 Hz
- Vortex Freq (0.2-0.4x): 2.0 - 4.0 Hz
LOAD-SHIFTING DIAGNOSTIC (MAPPING THE ZONE)
Adjust power from 20% to 100% in 5% increments.
Hold each load for 3 minutes to allow vortex stabilization.
Safe: <2.0mm /s | Warning: 2-4mm/s | Critical:>4mm/s.
Limit continuous run in Red Zone (>4.0mm/s) to < 2 hours. Request dispatch load shift immediately.
AIR INJECTION TUNING
Air admission disrupts vortex coherence. It's a precision tool, not just venting.
- Open valve in 10% steps at known rough loads.
- Find "Sweet Spot" with minimum vibration.
- Verify seasonal head changes (Monsoon vs Dry).
COMPRESSOR CAPACITY
50-100 Nm³/h @ 2.5 Bar
If pressure drops < 1.5 Bar during injection, compressor is undersized.
ACOUSTIC DIFFERENTIAL DIAGNOSIS
| SOUND SIGNATURE | LIKELY CAUSE | IMMEDIATE ACTION |
|---|---|---|
| Low Hz "Whump" (2-4Hz) | Draft Tube Vortex Rope | Increase Air / Shift Load |
| High Hz "Whine" (>100Hz) | Cavitation / Bearing Scoring | Check temps / Lubrication |
| Intermittent "Bang" | Debris Impact / Loose Bolt | EMERGENCY STOP - INSPECT |