Gas dynamic analysis of the performance of diffuser augmented wind turbine

A diffuser augmented wind turbine (DAWT) is considered an important application of the advanced concepts to improve the attractiveness of wind energy. The present paper aims to find a theoretical demonstration of DAWT by using theoretical analysis, mathematical models, assumptions, estimations and maximization of power coefficients and augmentation ratios, in addition to computer programs for calculations and drawings. The final results show that the maximum power coefficient (Cpd0) and augmentation ratio (Rb-) relative to Betz — are directly proportional to pressure recovery factor(Cr), turbine factor (Ct), and maximum velocity ratio(No), but inversely proportional to overall recovery factor (Co) of diffuser. The power coefficient(Cpd0) of DAWT reaches 1.5 at C0 ≃ -0.5,No ≃ 1.0 andCr ≃ 0.5, but the augmentation ratio(Rb) reaches 6.0 at C0 ≃ -0.5,Cr ≃ 0.9, and reaches 7.0 atNo ≃ 1.0 and Ct ≃ 1.0, which gives a good application for DAWT systems.