![[Bernoulli's equation derivation]] - There are many forms of Bernoulli's eqn. depending on assumptions used - Bernoulli's eqn. tells us that the constant obtained at position 1 is the same at position 2 (only along the same streamline) - Similar to a CoE equation, $\frac{p}{\rho}$ is like "pressure work" - Common to divide by $g$: $\frac{p}{\rho g}+\frac{V^2}{2g}+z=\text{const}$ - $\frac{p}{\rho g}$: static pressure head - $\frac{V^2}{2g}$: velocity head - $z:$ elevation head - Another common form: $p+\frac{1}{2}\rho V^2+\rho gz=\text{const}$ - $p:$ static pressure - $\frac{1}{2}\rho V^2$: dynamic pressure - $\rho gz$: hydrostatic pressure (often neglected) - Can consider inviscid if small velocity gradient or elevation change, $\tau=\mu \frac{du}{dy}$