Design with the Big D

Gas Turbine Engines (GTEs)

• Turbojet
  • 燃烧室
• Turboprop
  • 加速度比 turbojet 小
• Turbofan
  • 长距离飞行
  • 大部分推力来自 bypass air
  • 为了使压缩机工作，还有部分空气

2000 \(^\circ\)C

Structural Integrity of GTEs

Constituents of GTEs

Blade attachment

• Compressor Disc
  • Dove Tail
  • Fatigue
• Turbine Disc
  • Fir-tree rim
  • Creep + Corrosion

Two alternative failures:

• Bursting of a disc
• Blade shedding

Contact stress between blade and disc (Dovetail region)

Blade shedding in Aviation GTEs

Rolls Royce 测试：使用爆炸物把叶片炸掉，发动机还能支撑十几秒

Bird Strikes

Bird strikes represents 90% of FOD (Foreign Object Damage).

Aerial Refueling

Hose instability

explosive decompression：类似于扎破气球，应力瞬间释放。解决方法：在气球上粘上一段胶带，应力传递到胶带上 \(\implies\) Fuselage 的壳层有两层