Numerical investigation of a variable stator vane with nonuniform partial radial gaps in an annular compressor cascade

Abstract A variable stator vane (VSV) with nonuniform partial radial gaps is numerically investigated in an annular compressor cascade. Five adjusting angles (α = −5.5°, −5°, 0°, 5° and 10°) are chosen to simulate different working conditions. The VSV is adjusted in negative direction means that the stagger angle increases and the VSV is more closed. Since the VSV is installed in an annular cascade, the heights of the partial gaps are nonuniform and reaches 3.8% of the span. Results show that as the VSV is adjusted negatively, the total pressure loss rises by 20.3% and a huge area of corner separation appears. The outflow angle is also more distorted along radial direction. Comparisons with a fixed-configuration stator show that although the VSV would cause higher loss, it indeed plays an important role in adjusting the outflow angle.