Analysis of Oscillation Effects on HotStreak Migration Characteristics in Turbine Vane Passage

ABSTRACT

The high pressure turbine is subjected to the inlet hot gas resulting from the combustor, which is generally non-uniform. The strong non-uniform temperature at the turbine inlet is known as “hotstreak.” Although many studies have been performed to investigate the hotstreak migration in the turbine vane passage, the HS is generally modeled to be steady and there are relatively few studies on the unsteady oscillating hot streak (OHS). The present study performs numerical investigations on the oscillation effects on the HS migration characteristics. The OHS is modeled to be oscillating in the circumferential direction, with varying oscillation magnitude and frequency. The steady hot streak (SHS) is modeled to be positioned at the guide vanes. Comparisons between the SHS and the OHS are conducted in detail regarding the flow and heat transfer characteristics. Both of the two cases of HS are based on the NASA experiment report and the No. 4313 case in the experimental design is selected. It is found that the change of HS from steady to oscillating leads to significant differences of transient periodic fluctuating characteristics of heat load and pressure on the guide vane. The HS areas are increased significantly and the mean temperature is decreased correspondingly. The introduction of oscillation effects is found to merit a better prediction of the real HS migration features in the real turbine passage.

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China (grant No: 51606095), the Jiangsu Provincial Natural Science Foundation (grant No: BK20160794), the Foundation of Graduate Innovation Center in NUAA (No: kfjj20160202) and the Fundamental Research Funds for the Central Universities.

Notes on contributors

Mingfei Liu

Mingfei Liu is a Master student at Nanjing University of Aeronautics and Astronautics, Nanjing, China, under the supervision of Prof. Junkui Mao and Prof. Xingsi Han. He received his Bachelor degree in 2015 from Taiyuan University of Technology. He is currently working on hotstreak in gas turbines and infrared thermometry technology.

Junkui Mao

Junkui Mao is a Professor of thermal science of aero-engines at Nanjing University of Aeronautics and Astronautics, Nanjing, China. He received his Ph.D. degree from Nanjing University of Aeronautics and Astronautics in 2003. His main research interests include thermal management and high efficient cooling technology in aero-engines, thermal analysis of secondary air system, tip clearance active control, and numerical simulation. He has published more than 50 journal papers.

Xingsi Han

Xingsi Han is a Professor at Nanjing University of Aeronautics and Astronautics, Nanjing, China. He received his Ph.D. degree from University of Science and Technology of China in 2009. He mainly works on high-fidelity simulation of complex thermal fluids, including cooling process, turbulent combustion, complex turbulent flow, and flow control. He has published more than 40 journal and conference papers.