Parameterized feature modeling and aerodynamic optimization of centrifugal compressor based on NURBS

According to feature-based modeling technology, the parameterization method for centrifugal compressor with vane diffuser is studied. Impeller is decomposed to two features, blade and turntable. Radial blade profile is presented by non-uniform rational B-spline, and blade is obtained by ruled surface method. Diffuser blade profile is created by the quintic polynomial method with continuous three order derivatives, and the blade is created through profile sketch extending at hub. With the second development module of computer aided design system, automatic modeling of centrifugal compressor is accomplished. Taking angle of control pole of radial blade profile and assembly angle of diffuser blade as design variables, aerodynamic optimization is driven by then combination of global and local optimization arithmetics. The result shows that the performance of compressor is improved and radial blade profile after optimization present slant feature.