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Int. J. Turbomach. Propuls. Power 2018, 3(1), 1;

Simulation of Indexing and Clocking with Harmonic Balance

Institute of Propulsion Technology, Linder Höhe, German Aerospace Center (DLR), 51147 Cologne, Germany
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
This paper is an extended version of our paper published in Proceedings of European Turbomachinery Conference ETC12 2017, Paper No. 135.
Academic Editor: Wolfgang Sanz
Received: 9 November 2017 / Revised: 15 December 2017 / Accepted: 15 December 2017 / Published: 22 December 2017
PDF [2624 KB, uploaded 24 December 2017]


The aim of this paper is to demonstrate how the harmonic balance method can be used to predict rotor–rotor and stator–stator interactions in turbomachinery. These interactions occur in the form of clocking and indexing. Whereas clocking refers to the dependency of the performance on the relative circumferential positioning of the rotors or stators, the term indexing is used when different blade (or vane) counts lead to an aperiodic time-averaged flow. The approach developed here is closely related to the one presented by He, Chen, Wells, Li, and Ning, who generalised the Nonlinear Harmonic method to zero-frequency disturbances. In particular, configurations with only one passage per blade row are used for the simulations. We validate the methods by means of the simulation of a fan stage configuration with rotationally asymmetric inlet conditions. It is demonstrated that the harmonic balance solver is able to accurately predict the inhomogeneity of the time-averaged flow field in the stator row. Moreover, the results show that the approach offers a considerable gain in computational efficiency. View Full-Text
Keywords: harmonic balance; turbomachinery; computational fluid dynamics; clocking; indexing harmonic balance; turbomachinery; computational fluid dynamics; clocking; indexing

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Frey, C.; Ashcroft, G.; Kersken, H.-P.; Schönweitz, D.; Mennicken, M. Simulation of Indexing and Clocking with Harmonic Balance. Int. J. Turbomach. Propuls. Power 2018, 3, 1.

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Int. J. Turbomach. Propuls. Power EISSN 2504-186X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
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