A detailed review and analysis of the thermal-hydrodynamic characteristics in air-cooled compact wavy fin heat exchangers is presented. New models are proposed which simplify the prediction of the Fanning friction factor f and the Colburn j factor. These new models are developed by combining the asymptotic behavior for the low Reynolds number and laminar boundary layer regions. In these two regions, the models are developed by taking into account the geometric variables such as: fin height (H), fin spacing (S), wave amplitude (A), fin wavelength (λ), Reynolds number (Re), and Prandtl number (Pr). The proposed models are compared with numerical and experimental data for air at different values of the geometric variables obtained from the published literature. The new models for f and j cover a wide range of the Reynolds number. Since the model is based analytically, it will also allow for proper design assessment of heat exchanger performance.