# Static pressure versus stagnation pressure Often a source of confusion, we can use Bernoulli to explain the terminology around static pressure and stagnation pressure. Bernoulli states that for incompressible, inviscid flow, the sum of static pressure, dynamic pressure (or velocity head), and hydrostatic pressure is constant along a streamline (ignoring irrecoverable frictional losses). $\underbrace{\underbrace{\quad P\quad}_\text{Static}+\underbrace{\quad\frac{1}{2}\rho v^2\quad}_\text{Dynamic}}_\text{Stagnation}+\underbrace{\quad\rho gh\quad}_\text{Hydrostatic}=\text{CONST}$ Stagnation pressure (or 'total' pressure) is the pressure that a fluid possesses when it is brought to rest and is the sum of static pressure and dynamic pressure (stagnation pressure is always 
$\geq$ static pressure). Static pressure is the pressure that would be measured by a gauge/instrument on a flowing line. Static pressure can increase in a piping system over components such as expanders due to the decrease in fluid velocity. > [!info] Video > Also see this great [video](https://www.youtube.com/watch?v=n7SnDlYjDyo) on the topic from AFT. > ![[static_versus_stagnation.png]]