11th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
This paper presents two numerical methods allowing unsteady blade row simulations with a reduction of the computational domain to one blade passage per row: the multiple frequency phase-lagged approach and the harmonic balance time approach implemented in elsA CFD code. The first part of the paper reminds the principle of the two methods, their main hypothesis and their theoretical limitations. The second part of the paper presents the application of these two methods on the 3.5 stage axial experimental compressor CREATE investigated at Ecole Centrale de Lyon in LMFA laboratory. The results obtained with the simplified unsteady models are analyzed and compared to an unsteady reference multiple passage computation and with a steady mixing plane approach. The comparison of these results enables to highlight the interests of these two unsteady numerical approaches and also to underline their limits.