Abstract: The inland and overseas advance and current status of the investigation into internal flow of turbomachinery are reviewed in terms of theoretical analysis, experiments and numerical simulation respectively. The classification, definition and investigation status of internal flow losses of turbomachinery are outlined at first. The theoretical development of internal flow of turbomachinery is then summarized in terms of separation theory, vortex dynamics and flow pattern. The advance of experimental investigations of turbomachinery is reviewed in terms of linear cascade, annular cascade, unsteady experiment and measurement techniques. The methodology, content and achievement of numerical simulation are summarized in terms of govern equation, numerical technique and grid creation. The ap-proaches to improve the aerodynamic performance of turbo-machinery are reviewed and the perspective of this research field is conducted finally. The results show that the investigation into the internal flow of turbomachinery has achieved great improve-ment and many achievements have been implemented in the de-sign, and more in-deep study is still needed in this field.

Key words: Internal flow, Review, Turbomachinery