Stagnation point

This information can be used to show that the pressure coefficient ${\displaystyle C_{p}}$ at a stagnation point is unity (positive one):[1]^{:§ 3.6}

${\displaystyle C_{p}={p-p_{\infty } \over q_{\infty }}}$

where:

${\displaystyle C_{p}}$ is pressure coefficient

${\displaystyle p}$ is static pressure at the point at which pressure coefficient is being evaluated

${\displaystyle p_{\infty }}$ is static pressure at points remote from the body (freestream static pressure)

${\displaystyle q_{\infty }}$ is dynamic pressure at points remote from the body (freestream dynamic pressure)

Stagnation pressure minus freestream static pressure is equal to freestream dynamic pressure; therefore the pressure coefficient ${\displaystyle C_{p}}$ at stagnation points is +1.[1]^{:§ 3.6}

On a streamlined body fully immersed in a potential flow, there are two stagnation points—one near the leading edge and one near the trailing edge. On a body with a sharp point such as the trailing edge of a wing, the Kutta condition specifies that a stagnation point is located at that point. The streamline at a stagnation point is perpendicular to the surface of the body.

• Stagnation point flow