Predicting stall delayed performance of rotating HAWT and its inherent mechanical driving forces

Abstract

A conceptual HAWT analysis model was proposed to predict flow's pressure distribution upon blade surfaces and the lifting forces along blade span under stalling conditions. Compared with 2D static measured data, delayed stall is captured with evident phenomenon and exhibited the validated model analysis ability. From the results it is also shown that along blade profile Coriolis force has the same magnitude to centrifugal force, and its direction may vary with the stalled level of relative flow. Different levels of both forces along blade span result in varied spanwise boundary flow pattern. Three dimensional delayed stall can then be explained in quantity for rotating HAWT blade profile.