Abstract
Engines and, thus, the compressor suffer operational, particlebased wear during operation depending on ambient conditions and particle size. Fouling describes the deposition of small particles on the blade surfaces leading to an increased blade thickness, surface roughness, and changed geometry. In experiments, the effect of fouling in the compressor is evaluated. Rough stator vanes are distributed equally spaced around the circumference or clustered within a stator row. The worn vanes are coated with a randomly distributed surface structure of hemispheres representing fouled vanes. The roughness parameters of the coating are based on measurements from a CFM-56 engine. The results show a better integral flow field for a non-uniform distribution. Losses in adjacent passages of the rough vanes are visible in wake flow measurements. Therefore, one-third of coated vanes, equally spaced around the circumference, are responsible for almost two-thirds of the efficiency losses of an entire rough stator row.
