List of equations in fluid mechanics

This article summarizes equations in the theory of fluid mechanics.

t ^

is a unit vector in the direction of the flow/current/flux.

ρ

{\displaystyle \mathbf {F} _{\mathrm {b} }=-\rho _{f}V_{\mathrm {imm} }\mathbf {g} =-\mathbf {F} _{\mathrm {g} }\,\!}

Apparent weight

{\displaystyle \mathbf {W} _{\mathrm {app} }=\mathbf {W} -\mathbf {F} _{\mathrm {b} }\,\!}

∂ ρ

ρ

= ρ

Flux F through a surface , d S is the differential vector area element, n is the unit normal to the surface. Left: No flux passes in the surface, the maximum amount flows normal to the surface. Right: The reduction in flux passing through a surface can be visualized by reduction in F or d S equivalently (resolved into components , θ is angle to normal n ). F •d S is the component of flux passing through the surface, multiplied by the area of the surface (see dot product ). For this reason flux represents physically a flow per unit area .