Reynold's Number
Osborne Reynolds was a late 19th century scientist who studied the flow of fluid within pipes looking at the conditions when flow transitioned between laminar and turbulent regimes.
$$ {Re} = {{\rho V L} \over {\mu}} $$
where:
\(\rho\) is the fluid density
\(V\) is the fluid velocity with respect to the object
\(L\) is a characteristic length
\(\mu\) is the dynamic viscosity of the fluid
Re is the ratio between inertial and viscous forces within a moving fluid. It ca be a useful tool in determining if a flow (within a pipe, say) will be laminar (smooth and steady) or turbulent (chaotic). It is also useful when scaling fluid dynamic problems.
Very roughly, low Re (\(<10^3\)) indicates that laminar flow will prevail whereas higher Re (\(>10^4\)) tends to indicate turbulent flow.
$$ {Re} = {{\rho V L} \over {\mu}} $$
where:
\(\rho\) is the fluid density
\(V\) is the fluid velocity with respect to the object
\(L\) is a characteristic length
\(\mu\) is the dynamic viscosity of the fluid
Re is the ratio between inertial and viscous forces within a moving fluid. It ca be a useful tool in determining if a flow (within a pipe, say) will be laminar (smooth and steady) or turbulent (chaotic). It is also useful when scaling fluid dynamic problems.
Very roughly, low Re (\(<10^3\)) indicates that laminar flow will prevail whereas higher Re (\(>10^4\)) tends to indicate turbulent flow.
