Boundary Layer Theory MCQ with answer and solution

The nominal distance of a boundary layer is defined as the distance from the wall to a point

• AWhere the velocity is 99% less than the asymptotic limit
• BWhere the velocity ceases to be laminar
• CWhere the velocity is within 90% of the asymptotic limit
• DWhere the velocity is 99% of its asymptotic limitCorrect

Solution

Concept

Nominal thickness

Step-by-step solution

1. δ is the distance where u = 0.99 U.

Explanation

The velocity is 99% of the free stream velocity.

Why the other options are wrong

Others misuse the definition.

Shortcut

δ at 99%.