Clocking effect of compressor with different axial gaps part - Overall performance

The experimental investigation of stator clocking effect with different axial gaps shows that the variation of efficiency increases while the mass flow rate increases at fixed axial gap, but the pressure ratio changes little. The efficiency at design point becomes maximum at 67% axial gap and minimum at 33% axial gap. But the clocking positions corresponding to the maximum and minimum efficiency change at different axial gaps. Under the combined effects of clocking position and axial gap, efficiency improves 1.0% at most at design point and 2.3% at the maximum mass flow point. However, surge margin decreases as the axial gap reduces.