Investigation of the Effect of the Geometric Deviations on the Performance of a Radial Flow Compressor Employing Uncertainty Quantification (UQ) and Sensitivity Analysis

The performance of the impeller of a radial flow compressor is highly affected by its geometric uncertainties. The geometrical characteristics of the impeller may change slightly during the manufacturing process or as a result of long-term operation, resulting in deviations from design performance curves. In this research, the performance sensitivity to each geometric parameter is determined using global sensitivity analysis, and the performance deviation interval is extracted using uncertainty quantification by the Kriging surface response method. For this purpose, initially, three categories of databases with a different number of impellers are created using geometric characteristics deviating from the original sample. For different geometries, the flow simulation in the impeller is performed using computational fluid dynamics in a viscous three-dimensional turbulent solver. A surrogate model which uses the Kriging method for each database to quantify the uncertainty more quickly is utilized. The results show that in 95.5% of cases, the pressure ratio and total to total efficiency and total to static efficiency fluctuate by 1.88%, 1.03%, and 1.56% around the predicted value, respectively. Moreover, the impeller's outlet radius is the most sensitive geometric parameter.