Transport II Dimensionless Groups

Biot Number

Drag Coefficient

Froude Number (Fr)

Definition of Biot Number

external heat transfer/internal heat transfer

Definition of Drag Coefficient

Drag/inertial forces

Froude Number Definition

inertial forces/gravitational forces

Grashof Number (Gr)

Grashof Number Definition

buoyancy due to thermal expansion/viscous dissipation

Nusselt Number (Nu)

Nusselt Number Definition

total heat transfer/conductive heat transfer

Peclet Number (Pe)

Peclet Number Definition

convection/diffusion

Prandtl Number (Pr)

Definition of Prandtl Number

momentum diffusivity/thermal diffusivity

Rayleigh Number (Ra)

Definition of Rayleigh Number

buoyancy due to thermal expansion/dissipation

Reynolds Number (Re)

Definition of Reynolds Number

inertial forces/viscous forces

Womersley Number (alpha)

Womersley number Definition

penetration depth/tube length

=Nu/(RePr)

Stanton Number

Stanton Number Definition

heat transfer/convective heat transfer

fanning friction factor

definition of fanning friction factor

wall shear stress/dynamic pressure

= ff/2

Colburn Analogy

h=~ p*Uinf*Cp(ff/2)Pr^(-2/3)

Colburn Analogy

Schmidt Number (Sc)

Definition of Schmidt Number

momentum diffusivity/mass diffusion