Abstract: The dynamic stall process of DU91-W2-250 blade section with delta wing vortex generators（VGs）is studied by using the k-ω SST turbulence model. The effect and law of the chordal position of VGs（ x/c）on the dynamic stall inhibition is analyzed from the aspects of the lift and drag coefficient,surface pressure coefficient,flow field and the development process of VGs shedding vortex. The results show that x/c has a great influence on the lift increase effect during the dynamic stall of airfoil,and VGs increase the stall angle of attack of airfoil. The results of lift,resistance and pressure show that when x/c = 0.25,the lift increase effect is the best,and the Cp on the upper surface of the blade section is larger. When x/c = 0.20-0.25,the trailing edge adhesion flow is better. From the change of vorticity peak value,when the value of x/c is too large or too small,the inhibition effect of VGs on separated vortex is weakened.According to the variation of VGs shedding vortex,when x/c = 0.20-0.25,the shedding vortex intensity is relatively large downstream of VGs,and the vortex dissipation velocity is slow. In conclusion,when the VGs are installed at x/c = 0.20-0.25,the aerodynamic performance of the blade section can be improved best.