<p>The coupling between different components of a turbomachinery, e.g. between the combustion chamber and high-pressure turbine, is becoming more widely studied especially by use of numeric. In this specific numerical context, Large-Eddy Simulation has appeared as a credible candidate to perform such simulations to consider fully integrated with both two-way temporal and spatial coupling between two given components: i.e. a combustor with its first stage turbine or a compressor interacting with the combustor. Such simulations are of particular interest especially at the interface between a combustion chamber and a turbine, for which the prediction of the transport of hotspots generated in the chamber is of paramount importance for performance and life-duration issues. Despite the need of fully coupled simulations, typical turbomachinery simulations only consider isolated components with mean 0D, 1D or 2D quantities imposed at their boundaries preventing any accurate two-way coupling. The objective of the paper is to study available solutions to perform isolated simulations while taking into account the effect of multi-component coupling. The injection of synthetic turbulence is one of the solution that can be looked at. However, as shown in the present paper, the method does not allow an accurate reproduction of the coupling between a chamber and a turbine, as it is unable to reproduce proper temperature-velocity correlations or other physical phenomena. Here, the FACTOR configuration is considered, composed of a combustor simulator followed by a single stage HP-turbine. Thanks to this reference and fully coupled first LES, the data at the interface plane between the chamber and the turbine is recorded and made available. Then, using the Spectral Proper Orthogonal Decomposition method, the recorded data is partially reconstructed using different numbers of frequencies. From the partial reconstructions, isolated simulations are performed by injecting the reconstructed databases at the turbine inlet. The reference coupled simulation is then compared to the isolated simulations with partial inlet condition reconstructions and averaged quantities with or without synthetic turbulence injection. The isolated simulations for which the inlet condition is reconstructed with a large number of frequencies show very good agreement with the reference fully coupled simulation compared to the typical isolated simulation with average quantities imposed at the inlet. As expected, decreasing the number of frequencies in the reconstructed signal deteriorates the accuracy of the data. However, isolated simulations with a low number of frequencies still perform better compared to standard isolated simulations since the global behavior and fluctuations of the flow is better captured by the partial reconstruction.</p>

Accurate Inlet Boundary Conditions to Capture Combustion Chamber and Turbine Coupling With Large-Eddy Simulation

Paper Proceedings: https://asmedigitalcollection.asme.org/GT/GT2021/volume/84898

Turbo Expo 2021

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.