Streamwise Evolution of Loss in a Shrouded Axial Compressor Cascade Passage

Abstract

DOI: 10.2514/1.B34006 Streamwise evolution of blade passage flows, including loss and flow turning, has been characterized experimentally and numerically. Experimentally, to simulate rotation effects in a shrouded axial compressor linear cascade, the leakage flow in the shrouded seal cavity is artificially circulated through a secondary flow loop connecting bothsidewalls of the shrouded cavity. The overall lossand deviation have been measured downstream of the stator blade row at the design point, and the results compare well with the data from a rotating environment. To gain further physical insights into how the passage flow near the blade/endwall surfaces behaves at the downstream cavity trench, numerical simulation has been conducted. Detailed flow data obtained from the experiment and numerical simulation consistently demonstrate that the loss is successively increased from the leading edge up to the upstream edge of the downstream cavity trench. As the mainstream passes over the downstream cavity trench, however, the loss is decreased as the high-loss fluids concentrated near the hub endwall are engulfed into the downstream cavity. Downstream of the blade row, the loss increases again due to the wakes from the trailing edge of the stator blade.