CREATE: Advanced CFD for HPC Performance Improvement

The present paper provides an overview of technological evolutions aimed at improving the aerodynamic performance of Snecma’s High Pressure Compressors. Several concepts were investigated under its CREATE compressor research program, involving an extensive simulation effort. An overview of the computational approaches involved in the evaluation and selection of innovative and most promising concepts will be given in the paper. The main topics dealt with are:1) Aeromechanical optimization of airfoils and flow path:In recent years, great efforts have been made to improve the aerodynamic design of airfoils. Among them, optimization methods have been progressively implemented in the design process with an increased complexity logic. The latest methods used at Snecma involve multi-objective, multi-parameters aeromechanical optimization including mean camber line, stacking axis, flow path contouring and more. This work is illustrated by two practical examples.2) Vortex generators:In order to control the flow, vortex generators can be forecasted as a promising step forward. The goal is to create exogenous vorticity that will counter-balance the endogenous vorticity. Thus they appear as a tool to reduce losses and improve stability in highly loaded turbomachinery devices such as modern high pressure compressors. This section of the paper will give an overview of the dedicated numerical simulations completed.3) Clocking:Numerous studies are related to the benefit drawn from turbine clocking on turbomachinery performance. However, fewer examples of successful compressor clocking exist. The recent capability of computational fluid dynamics tools to reduce the computational effort necessary to investigate such an issue (by the use of harmonic balance methodology) gives the opportunity for a renewed evaluation.4) Optimization of shroud leakage flow with main flow:A strong interaction exists with the secondary flows originated in the inner flow path cavities. Coupled main flow path and cavities aerodynamic simulations were conducted to improve the relevance of the computations and understand the mechanisms involved.5) Tandem bladings and splitters in axial rotors:The last aspect of the study was focused on dual blading concepts. After a brief review of the literature, some simulations were carried out to explore the relevance of such concepts from the viewpoint of modern high pressure compressors performance improvement.Copyright © 2012 by ASME