Features оf heat transfer processes on turbine blade surfaces in gas turbine engines

Аuthors

Grigorovsky V. V.^*, Kotovich I. V., Ezhov A. D.^**, Suchkova P. I.

Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia

*e-mail: grislavapro@gmail.com
**e-mail: ezzhov@gmail.com

Abstract

The presented article is devoted to an in-depth analysis of scientific research concerning thermogasdynamic processes and heat exchange phenomena between high-temperature gas flows and working elements of gas turbine engines (GTE), in particular, blades. Attention is focused on the study of the complex interaction of high gas temperatures with the surfaces of turbine blades, a key factor that determines the operational characteristics, reliability and durability of modern aviation and power plants. Based on the generalization of experimental data and numerical modeling, the structure of the boundary layer formed at the interface between a high-temperature gas and the cooled surface of the blade is analyzed in detail. It is emphasized that the development of the boundary layer passing through various stages, from the laminar to the turbulent regime, has a direct effect on the level of local heat exchange intensity and the distribution of temperature fields inside the blade material. This is especially important because the optimization of heat exchange processes reduces the thermal loads on the blades and increases the service life of the entire unit. Special attention is paid to the consideration of the criterion dependences used to model convective heat transfer under conditions of extremely high thermal loads and complex dynamics of the gas dynamic field. These dependencies play an important role in predicting the behavior of blade materials and allow for a more accurate assessment of cooling parameters, such as the rate of heat removal and temperature distribution along the blade surfaces. The final conclusion highlights the importance of efficient cooling of turbojet engine blades, which helps to significantly increase their reliability and extend their service life at elevated temperatures in the combustion chamber. However, there are still a number of urgent problems that require further indepth research on both experimental and theoretical levels. For example, one of the key unresolved issues remains the issue of safe operation of gas turbine blades at a gas flow temperature exceeding 2500 K. At the same time, the development of new materials and coating technologies that provide high resistance to erosion and oxidation when exposed to an aggressive environment of hot gases is of particular importance. The need to take into account interdisciplinary aspects such as fracture mechanics, heat resistance, and the interaction of mechanical stresses with the thermal field requires an integrated approach to solving the tasks set.

Keywords:

turbine blade, gas turbine engine, boundary layer, heat transfer, thermal protection

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