Executive Summary : | Gas turbine engines operate in environments that are susceptible to blade surface erosion or deposition, resulting in surface roughness. Understanding surface roughness can aid in predicting maintenance intervals, devising cost-effective repair strategies, and developing better engines. While previous studies have explored areas such as tandem design, inflow distortion, stall inception, tip gap effect, and sweep, there are unexplored aspects, particularly regarding the effect of surface irregularities encountered during tandem-stage operation.
This proposal aims to enhance understanding of tandem rotor flow physics under various surface roughness conditions through experimental and numerical simulations (using ANsYs CFX software). steady RANs simulations will visualize the complex flow features of the tandem rotor, while performance quantification will provide guidelines for future designs. Detailed assessments of the design will lead to an improved understanding of the tandem rotor and its application in future compressor designs. The performance of the tandem bladed stage under different patterns of surface roughness will be measured and systematically documented. The performance penalties in terms of pressure rise, efficiency and stability margin will be established through detailed experiments. Further, CFD analysis will be carried out to have a better understanding of the complex flow features associated with such configurations. Based on this, better design strategies to minimize in-service effects such as surface roughness, can be evolved. The proposed work will also generate an extensive test database that can be used for validating CFD results in such complex flow situations. |