functionGrashofNumber

Returns Grashof number

Extends from Modelica.Icons.Function (Icon for functions).

Information

Often takes a role in natural convection prcoesses that Reynolds number does in forced convection.

Defined to be the ratio of the buoyancy forces to the viscous forces acting on the fluid.

  • Ja = cp*(Ts-Tsat)/h_fg


If Gr/Re^2 ~= 1 then free and forced convection must be considered.

If Gr/Re^2 << 1 then free convection effects may be neglected.

If Gr/Re^2 >> 1 then forced convection effects may be neglected.

Inputs

TypeNameDefaultDescription
SI.LengthxPosition for local Gr_x or characteristic surface length Gr_L
SI.PrandtlNumberPrPrandtl number
SI.TemperatureT_wallWall temperature
SI.SpecificHeatCapacitycpSpecific heat capacity
SI.TemperatureTsSurface temperature
SI.TemperatureTsatSaturation temperature
SI.SpecificEnthalpyh_fgLatent heat of vaporization

Outputs

TypeNameDefaultDescription
Units.NonDimJaJakob number