Coastal Texas Tracker Array Aeroelastic Flutter Event

Sustained flutter observed at 14–18 m/s winds, causing actuator lockups and module delamination

🏗️ Project Overview

350MW coastal site with salt-corroded torque tubes and unshielded exposure

🎯 Challenge

Sustained flutter observed at 14–18 m/s winds, causing actuator lockups and module delamination

🔧 Design Approach

Installed vortex suppression strakes (12 mm height, λ/D = 0.18); replaced corroded tubes with 316SS; added pitch-rate limiting firmware

📐 Design Diagram

_f = 12.3 → 22.8 m/s+10.5 m/s marginFlutter Event14–18 m/s316SS TubesPitch-Rate LimitStrakes Installed

AI-generated project design illustration

📐 Key Calculations

Strouhal Number Match

St = f·D/V

Result: 0.172 (target), 0.175 (achieved)

Shifted shedding frequency out of resonant band

Critical Flutter Velocity

V_f = π·f_n·D/(2·St·√(ρ·k))

Result: 12.3 m/s → 22.8 m/s

Raised threshold above 95th-percentile wind speed

📊 Results

Flutter eliminated; actuator failure rate dropped from 21/yr to 0; 3-year ROI on strake retrofit

💡 Lessons Learned

• •Corrosion reduces effective stiffness more than strength — requires dynamic re-evaluation
• •Pitch-rate limiting must be coordinated with structural DAF to avoid control-induced resonance

✅ Key Takeaways

• 1Corrosion reduces effective stiffness more than strength — requires dynamic re-evaluation
• 2Pitch-rate limiting must be coordinated with structural DAF to avoid control-induced resonance