What is produced by wind flow around obstacles such as terrain or buildings?

What is produced by wind flow around obstacles such as terrain or buildings?

• A. Laminar flow
• B. Stable stratification
• C. No change
• D. Mechanical Turbulence

Answer: (D)

When wind meets obstacles like terrain or buildings, the smooth flow is disrupted and breaks into irregular, swirling motions in the wake. This is mechanical turbulence—the airflow is physically stirred by the obstacles, creating eddies, gusts, and increased turbulence intensity. Laminar flow describes smooth, orderly motion, which doesn’t occur around rough or sharp-edged obstacles where flow separation and mixing happen. No change wouldn’t fit because the presence of obstacles definitely alters the wind. Stable stratification involves density differences that affect vertical mixing, but the immediate effect of obstacles is the generation of turbulent, chaotic flow patterns.

When wind meets obstacles like terrain or buildings, the smooth flow is disrupted and breaks into irregular, swirling motions in the wake. This is mechanical turbulence—the airflow is physically stirred by the obstacles, creating eddies, gusts, and increased turbulence intensity. Laminar flow describes smooth, orderly motion, which doesn’t occur around rough or sharp-edged obstacles where flow separation and mixing happen. No change wouldn’t fit because the presence of obstacles definitely alters the wind. Stable stratification involves density differences that affect vertical mixing, but the immediate effect of obstacles is the generation of turbulent, chaotic flow patterns.