Abstract:
A non-axisymmetric inlet distortion problem exists in a boundary layer ingesting propulsion
system, which seriously affects the aerodynamic performance of the fan. This work presents an in-depth analysis of the fan stage under the influence of boundary layer ingestion. A high fidelity numerical approach is adopted to quantify the parameters that reduce the isentropic efficiency, total pressure ratio, and stability margin. At a later stage, an artificial neural network-based surrogate mathematical model is used in a multi-objective genetic algorithm to perform optimization. NASA stage 67 has been selected and validated against the experimental data. Entire annulus, steady-state, and three-dimensional modeling have been used for the combined analysis to analyze the effect of the inlet distortion on the fan stage. The numerical results indicated that the isentropic efficiency and total pressure ratio dropped by 9.49 % and 4.1%, respectively. The significant losses occurred at the suction side of the adjacent blade. Based on losses, trailing edge parameters are selected over the span near the blade's tip to ensure robust performance under the fan-face distortion. As a result of optimization, the isentropic efficiency and total pressure ratio improved by 2.88% and 1.69%, respectively. The optimization adds a value near the tip of the blade caused by the improvement of shockwave
