应能动学院流体机械及工程系、陕西省流体机械国际联合研究中心张楚华教授和琚亚平副教授邀请，法国里昂中央理工大学(EC-LYON)流体力学与声学实验室(LMFA) Xavier Ottavy教授将于2019年5月17-18日来访澳门新永利国际网站，访问期间将举行学术讲座，欢迎广大师生踊跃参加！（可盖章）
讲座主题 (Invited Lecture)：Research at LMFA for Turbomachinery: a Focus on Compressors (流体力学与声学实验室LMFA的透平机械及压气机研究进展)
内容简介：Turbomachinery is not a new subject in research, but the efforts provided to go ahead in this thematic have always been important. Today it is even more the case due to the fact that Turbomachinery needs to understand and integrate a lot of fundamental mechanisms in fields such as Fluid Mechanics, Turbulence, Thermodynamics, Acoustics, Mechanics, and their couplings. In order to design a compressor, not only its performance but also its operating range have to be predicted. This indeed has to be achieved within a level of confidence which becomes narrower with the complexity of the new machines. The tools to design a compressor are nowadays mainly based on Computational Fluid Dynamics. It starts with analytical modelling, continues with meridian and RANS simulations and sometimes uses Large Eddy Simulations in order to focus on specific features of the flow (even if these kind of simulations are still carried out in laboratories). Close to the end of the process experiments are always needed. First for an obvious need of validation of the design process, and of the prediction tools used, second to highlight and take into account and/or explain the coupling effects that the simulations cannot tackle.
Following this logic the goal of this presentation is to show how the LMFA participates in the research activities associated to compressors. The first part will be dedicated to the presentation of the Lab and the research topics on which the LMFA is focusing. The second part will present the experimental facilities and the numerical tools with their own specificities. The third part will address the topics of unsteadiness and instabilities. Here one of the major points concerns the characterisation of the basic structures (such as the tip leakage flow or the corner separation) that develop in a compressor blade channel and become deterministically unsteady when they change frame in rotors and stators. Some "fundamental" examples using Large Eddy Simulations and advanced experiments will be introduced. Some more realistic test cases installed on the LMFA's test rigs will demonstrate the importance of the coupling in the onset of instabilities. The last part will presents some elements about how to design test rigs and will try to summarize these research activities and their trends for the future.
Xavier Ottavy教授简介：Xavier Ottavy教授现任法国国家科学研究中心(CNRS)长聘研究员、CNRS/EC-LYON流体力学与声学实验室(LMFA)叶轮机械系主任，在压气机基础研究方向上主持完成了CREATE和PHARE-2等多个重要计划项目，是叶轮机械非定常非稳定流动、多学科优化设计与控制等研究领域的国际著名学者，与行业保持密切的产学研合作关系。
Prof. Xavier Ottavy is a permanent researcher at National Centre for the Scientific Research (CNRS) in France. Since 2016, he is at the Head of the Turbomachines Department at Laboratoire of Fluid Mechanics and Acoustics (LMFA) located at the Ecole Centrale de Lyon (ECL) in France.
After his PhD thesis in Fluid Mechanics (Turbomachines) at the Ecole Centrale de Lyon, Xavier Ottavy has been working as a Research Associate at the Cambridge University in the Whittle Lab. At the end of year 2000, he got his permanent researcher position at CNRS and joined the Turbomachinery Department of the LMFA, where he is working on the unsteadiness and instabilities in compressors. For its studies he uses low speed experimental test cases but also high speed tests rigs with realistic machines which need powers of several MegaWatts. In 2009, he became the supervisor of the CREATE Project (based on the 2MW test rig ECL-B2 with an high-speed multistage axial compressor), and in 2011 he started the project PHARE-2 (based on the 3MW test rig ECL-B3 dedicated to UHBR fans research in aerodynamics, aeroelasticity and acoustics fields). His projects are then based on experimental studies with some metrology and CFD developments, and are achieved with a strong connection with the industrials.
His research topics are:
- Unsteadiness and Instabilities in Turbomachinery
- Multiphysic Approaches for Turbomachinery
- Optimization and Control