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In this paper condensation heat transfer inside horizontal elliptical tubes is investigated for a stratified; concurrent two-phase flow of vapor and liquid. The
analysis takes into account the effects of
interfacial shear, axial pressure gradient, saturation temperature level and the development of the stratified angle associated with the accumulated condensate layer at the bottom of the tube. The governing equations are solved numerically with finite difference method. The results are presented for two 'cases; i.e. with and without fins. Also different values of ellipticity (b/a) are considered and discussed. At first, the results for special case of circle (b/a=l) are compared with available data in the literature that
shows good agreement. Also, comparing of obtained results for different values of ellipticity shows that for ellipticity values of less than one, condensation heat transfer
is greater than circular tubes; both above cases show greater transfer' than those corresponding to ellipticity values bigger than one.