Wind stagnation pressure, abbreviated as \( p_s \), also called stagnation pressure or total pressure, represents the maximum pressure a moving air stream can exert on an object. It is a basic concept derived from Bernoulli's principle, which states that the total energy along a streamline is constant for an ideal (incompressible and inviscid) fluid. When wind strikes a stationary object, such as the face of a building, the air velocity at the point of direct impact (the stagnation point) is brought to a theoretical standstill. At this point, the wind's kinetic energy (represented by the dynamic pressure) is completely converted into pressure energy.
Wind Stagnation Pressure formula |
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\( p_s \;=\; \dfrac{ 1 }{ 2 } \cdot \rho \cdot v^2 \) (Wind Stagnation Pressure) \( \rho \;=\; \dfrac{ 2 \cdot p_s }{ v^2 } \) \( v \;=\; \sqrt{ \dfrac{ 2 \cdot p_s }{ \rho } }\) |
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| Symbol | English | Metric |
| \( p_s \) = Wind Stagnation Pressure | \(lbf \;/\; in^2\) | \(Pa\) |
| \( \rho \) (Greek symbol rho) = Wind Density ( \(\rho \approx 0.00238\) ) | \(lbm \;/\;ft^3\) | \(kg \;/\; m^3\) |
| \( v \) = Wind Velocity | \(ft \;/\; sec\) | \(m \;/\; s\) |
The stagnation pressure is the sum of the static pressure of the free-flowing wind and its dynamic pressure. In practical terms for engineering, like designing wind resistant structures, this stagnation pressure represents the maximum possible positive pressure increase over ambient pressure that a given wind speed can generate on a windward surface, making it the basic pressure reference for all other wind load calculations.
