An inlet flow model of swept blades for streamline curvature through-flow methods

As a designing technique, blade sweep is currently widely utilized in the design of axial fans/compressors. The flow mechanisms of blade sweep has been extensively studied. In recent years, many studies have reported the incidence variation due to sweep, which can be attributed to the alteration of inlet radial equilibrium and axial velocity distributions induced by blade sweep. An inlet flow model of swept blades for streamline curvature through-flow methods is developed. The model takes into account the variation of inlet radial equilibrium due to blade sweep, without the hypothesis that the flow is uniform in the circumferential direction at the blade inlet. The model is applied for the design of a subsonic swept rotor blade, and the results show that in comparison with the original calculation, the model proposed can predict the distribution of axial velocity as well as the incidence angle more precisely. Therefore, the accuracy of design is improved with the model. Moreover, the effect of blade sweep on inlet radial pressure equilibrium is quantitatively analyzed.