Studies on lift-type VAWTs are far fewer than those on horizontal VAWTS, especially in the field of airfoil, which is regarded as the fundamental of VAWT design. Existing researches seldom systematically and efficiently touch upon a specific airfoil family. Thus, a coupled approach comprising two steps was used in this paper to assess an airfoil family, wherein the first step was the orthogonal algorithm combined with an automatic computational fluid dynamic analysis (ACFDA) module, and the second step was the combination of the one-factor at a time (OFAAT) algorithm and the ACFDA module. Results demonstrate that among three design parameters, the thickness-chord ratio (TCR) had the biggest effect on CP while the maximum thickness in tenths of chord (MTITOC) had the smallest influence on CP. By this approach, we found a desired airfoil having maximum power coefficient(CPMAX) was 0.4585, app. 15.5% higher than that of the previously widely used rotor NACA 0015. In addition, detailed flow data (field) dispersing in the vicinity of the airfoil were visualized to reveal the effect of each design parameter on airfoil's aerodynamic behavior. Lastly, this coupled approach can be used to assess any airfoil family that can be parameterized and has several design parameters. •Orthogonal algorithm was coupled with ACFDA module.•25 different airfoils were evaluated in this paper.•The impact weight of each design parameter was found.•15.5% more power coefficient was gained from a desirable airfoil.•A systematic and efficient evaluation approach for any Darrieus rotor's airfoil family.