The invention relates to a CAD (Computer-Aided Design) aided design method of a controllable diffused blade profile with curvature continuity, which belongs to the field of design of a
compressor blade. The method is characterized by comprising the steps of respectively solving a
leading edge point by using the point of tangency of a pressure surface, a
suction surface and a small circuit at the
leading edge; fitting with a cubic spline to solve the curvature of each
data point on the suction face and the pressure surface; solving a side profile of the suction face and a side profile of the pressure surface of the
leading edge with curvature continuity by a cubic Bezier curve; giving the curvature distribution of the suction face by a B spline curve to solve a
control point of the B spline curve, so that the deviation between the profile of the suction face with curvature continuity and the original profile of the suction face corresponding to curve distribution is minimum; and solving the position of the small circle at a
tail edge of the optimized blade profile. Compared with the original controllable diffused blade profile, the range of the
angle of attack is expanded by 2.5 degrees, and the pitot loss in a low loss area is reduced.