Eckert number

The Eckert number (Ec) is a dimensionless number used in continuum mechanics. It expresses the relationship between a flow's kinetic energy and the boundary layer enthalpy difference, and is used to characterize heat transfer dissipation. It is named after Ernst R. G. Eckert.

It is defined as

$\mathrm {Ec} ={\frac {u^{2}}{c_{p}\Delta T}}={\frac {\mbox{Advective Transport}}{\mbox{Heat Dissipation Potential}}}$

where

• u is the local flow velocity of the continuum,
• c_p is the constant-pressure local specific heat of the continuum,
• $\Delta T$ is the difference between wall temperature and local temperature.