Shear work contribution to convective heat transfer of dilute gases in slip flow regime

Moreover, to evaluate the inaccuracy of the results obtained by using the modified boundary conditions the difference, in terms of Nusselt number, between the exact and the approximate solution has been numerically estimated for elliptical microchannels. The numerical outcomes point out that the adoption of the modified boundary condition leads to an underestimation or an overestimation of the Nusselt numbers depending on the values of Brinkman number and on the channel cross section geometry.