What is the zone bounded by the separation streamline and a solid body's outer surface called__________________?
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Answer: A. wake
Explanation
The region of recirculating flow immediately downstream of a moving body bounded by separation streamlines is known as the wake. Flow separation occurs when adverse pressure gradients force boundary layers to detach from solid aerodynamic surfaces. Turbulent eddies within the wake generate significant pressure drag forces opposing the forward motion of the body. Fluid flow past blunt bodies creates boundary layer separation and distinct low-pressure wake zones behind them. Separation streamlines mark the boundary separating stagnant recirculating fluid inside the wake from free-stream flow. Wake characteristics determine the hydrodynamic and aerodynamic drag penalties experienced by moving vehicles.
Option B refers to drag forces, which measure overall resistance rather than the specific recirculating fluid zone. Option C denotes lift, which is the upward aerodynamic force acting perpendicular to incoming fluid flow. Option D represents the boundary layer, which is the thin shear region adhering directly to the solid body surface.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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