Novel slotted circumferential groove with self-recirculation boosts

A new study published in Scientific Reports, by researchers A.H. Ahadifard and H. Khaleghi, proposes a way to make transonic compressor rotors more stable. The team examines a slotted circumferential groove designed to generate its own internal flow recirculation pathway, aimed at reducing instability as compressors near their operating limits. Compressor stall and surge can sharply degrade air delivery to the combustor and increase mechanical and thermal loads. The work builds on casing treatments near rotor blade tips, where tip-leakage vortices and shock structures can distort flow. The paper focuses on the groove’s potential to expand stable operating margins without major added cost or complexity.