Turbine Mistuned Forced Response Prediction: Comparison With Experimental Results

Abstract

It is currently a major challenge for aeroengines manufacturer to be able to predict early in the design process the dynamic response of bladed disk. To guaranty a good accuracy of prediction, it is necessary to define properly the excitation (unsteady aerodynamics) and to take into account some phenomenon such as mistuning. This paper proposes an application of Snecma prediction method for mistune forced response on an experimental test case. The method used is a component modes synthesis method similar to the one proposed by Castanier and Pierre in 1997 [1] and validated against experiment in [2]. Some improvement have been performed to take into account more accurately the centrifugal forces effects in the projection basis and to couple the method with unsteady Computational Fluids Dynamic (CFD) codes. It is now possible to use this method in an industrial process. The method is applied to a HP turbine representative case, for which experimental results are available. These experimental results have been obtained in a European Community funded project dedicated to forced response study [3]. Mistuning effects have been measured. Moreover, a full characterization, of unsteady aerodynamics, aeroelastic and structural dynamics aspects have been performed. The results obtained with the proposed method are then compared to the experimental one. This application shows the consistency of the method and its efficiency.