Question

The relative thickness $\left(\delta /x\right)$ of turbulent boundary layer on a flat plate

• A. decreases with distance (x)
• B. increases with distance (x)
• C. remains constant
• D. depends on relative roughness

Answer 1

The correct option is A decreases with distance (x)

$\frac{\delta }{x}=\frac{0.376}{R{e}_x^{1/5}}$

As x increase,
$R{e}_x$ increase

$So\frac{\delta }{x}decreaseswithx.$