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The aerodynamic performance of original and modified airfoils with different camber for wind turbine was studied. The effects of relative camber on lift enhancement effect of blunt trailing-edge modification were revealed. The low-speed airfoil S809, S823 and S830 were modified to blunt trailing-edge airfoils of symmetrical trailing-edge thickness by XFOIL. The aerodynamic performance of original airfoils was simulated with S-A and k-ω SST turbulence model, respectively. And the numerical results were compared with the experimental data. Based on k-ω SST turbulence model with higher accuracy, the lift and drag coefficients, lift-drag ratios, their increments and airfoil surface pressure distributions of modified airfoils were calculated. The results showed that when the relative camber increased, the increment of lift coefficient increased first and then decreased in a certain range of attack angle, and the increment of lift-drag ratio increased before certain attack angle for blunt trailing-edge modification airfoils. The modified airfoil, whose relative camber was about 2.5% chord length, had the best lift enhancement effect, and the airfoil with large camber was unsuitable for the blunt trailing-edge modification.