@inproceedings{ReyVillazonWildowKuehhornetal., author = {Rey Villaz{\´o}n, Jos{\´e} Maria and Wildow, Toni and K{\"u}hhorn, Arnold and Benton, Robert and G{\"o}hler, Moritz}, title = {Impact of the Secondary Air System Design Parameters on the Calculation of Turbine Discs Windage}, series = {ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 5C: Heat Transfer, D{\"u}sseldorf, Germany, June 16-20, 2014, Paper GT2014-26050}, booktitle = {ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 5C: Heat Transfer, D{\"u}sseldorf, Germany, June 16-20, 2014, Paper GT2014-26050}, publisher = {ASME}, address = {New York, NY}, isbn = {978-0-7918-4573-8}, doi = {10.1115/GT2014-26050}, pages = {9}, abstract = {The rotating components in gas turbines are very highly stressed as a result of the centrifugal and thermal loads. One of the main functions of the secondary air system (SAS) is to ensure that the rotating components are surrounded by air that optimizes disc lifing and integrity. The SAS is also responsible for the blade cooling flow supply, preventing hot gas ingestion from the main annulus into the rotor-stator cavities, and for balancing the net axial load in the thrust bearings. Thus, the SAS design requires a multidisciplinary compromise to provide the above functions, while minimizing the penalty of the secondary flows on engine performance. The phenomenon known as rotor-stator drag or windage is defined as the power of the rotor moment acting on its environment. The power loss due to windage has a direct impact on the performance of the turbine and the overall efficiency of the engine. This paper describes a novel preliminary design approach to calculate the windage of the rotor-stator cavities in the front of a typical aero engine HP turbine. The new method is applied to investigate the impact of the SAS design parameters on the windage losses and on the properties of the cooling flows leading to the main annulus. Initially, a theoretical approach is followed to calculate the power losses of each part of the HPT front air feed system. Then, a 1D-network integral model of the cavities and flow passages of the HPT front is built and enhanced with detailed flow field correlations. The new 1D-flow network model offers higher fidelity regarding local effects. A result comparison between the theoretical calculation and the prediction of the enhanced flow network model puts forward the relevance of the local flow field effects in the design concept of the SAS. Using the enhanced 1D-flow network models, the SAS design parameters are varied to assess their influence on the windage and pumping power calculation. As a conclusion, the paper shows how the SAS design can have a significant influence on the HPT overall power and the air that is fed back into the turbine blade rows. Controlling these features is essential to bid a competitive technology in the aero engine industry. Copyright © 2014 by Rolls-Royce Deutschland Ltd \& Co KG}, language = {en} } @inproceedings{ReyVillazonWildowKuehhornetal., author = {Rey Villaz{\´o}n, Jos{\´e} Maria and Wildow, Toni and K{\"u}hhorn, Arnold and Benton, Robert and Eydam, Tobias}, title = {Advanced Turbine Preliminary Design Environment for the automatic Generation of Secondary Air System Models}, series = {ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7A: Structures and Dynamics Montreal, Quebec, Canada, June 15-19, 2015}, booktitle = {ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7A: Structures and Dynamics Montreal, Quebec, Canada, June 15-19, 2015}, publisher = {ASME}, address = {New York, NY}, isbn = {978-0-7918-5676-5}, doi = {10.1115/GT2015-42661}, abstract = {The design and development process of an aero engine is a complex and time-consuming task that involves many disciplines and company departments with different objectives and requirements. Along the preliminary design phase, multiple concepts are assessed in order to select a competitive technology. The engine design process, which was traditionally subdivided into modular component tasks, is nowadays considered as a multi-disciplinary workflow. Having recognized the need for developing advanced turbine preliminary design tools, this work focuses on enhancing the integration of turbine design disciplines, improving the accuracy of models and speeding the time to generate models. The proposed process facilitates an automated turbine Secondary Air System (SAS) and turbine discs concept definition. Furthermore, the process of CAD models and flow network models generation is accelerated via automation of the engineering workflow. This is accomplished through a novel Java based data model, where the design of turbine discs and SAS features is captured in a programmable framework. In the application section, the preliminary design definition of a reference HP turbine subsystem is replicated using the newly developed common design environment. The automated workflow is then used to generate the corresponding CAD models, recognize the subsystem flow network, and generate the 1D flow network model. The results are then compared to the experimentally validated model of a reference engine. As conclusion, the automated workflow offers a quick and parametric model generation process, while providing a good level of fidelity for the preliminary design phase. Copyright © 2015 by Rolls-Royce Deutschland Ltd \& Co KG}, language = {en} }