EFFECTS OF AUTOMATICALLY POSITIONING BLADE ON FLOW CHARACTERISTICS IN AN S-SHAPED AIR INLET

An automatically positioning blade with a NACA 0012-series profile was placed upstream near the throat of an S-shaped diffuser and experimented to investigate the characteristics of the flow behind it.The results show that two angular positions have been found where the blade experiences no resultant aerodynamic moment,i.e. 15° and -12°.Moreover,the swirls at the duct exit have different senses of rotation when the blade is held at these two angles.The study lays the foundation for suppression of the duct swirl and its simulation.