3D-modeling and simulation of transport and physicochemical transformations in a high pressure turbine of an aircraft engine

Abstract

Detailed investigation of aerothermodynamics and chemical processes in the high pressure turbine is challenging because of the complexities of 3D flow and kinetic chemistry relating to the moving blade at high temperature and pressure. We present herein, for the first time, new insights into the study of the 3D design, the tridimensional simulations of interaction between aerothermodynamics and chemical process, the evolutions of aerothermodynamics parameters under various operational conditions (Landing and Take-Off cycle), the chemical transformations of species (N-, S-, O-, H- and C-containing gases) in a high pressure turbine. For the first time, three numerical simulations based on 1D, 2D and 3D approaches of trace species transformations have been performed throughout an aircraft engine. We also shed light on the effect of 3D blade profile, radial spacing between blades, and rotation speed of rotor on the performance of a multi-row high pressure turbine. The vortex flow appearing in both rear stator blades and rotor blades has a strong effect on chemical transformation while the chemical processes could have also a relative impact on the flow parameters. As an example, calculations carried out with and without chemical reactions could reach variations up to 17 % for temperature field in the trailing edge of the rotor blades and 39 % for the velocity field, mainly located in the mixing plane of stator-rotor, in the trailing edge of the stator blades. Furthermore, our calculations indicate that the relationship between the aerothermodynamics parameters and the values of power setting is strongly convoluted. As an example, the thermal boundary conditions and rotor speed have strongly affected the temperature and velocity fields (14 % and 31 %, respectively). Contrary, the cooling system does not appear to affect the aerothermodynamics fields (about 2 %). Finally, the 3D simulations show strong inhomogeneities in chemical transformations throughout the turbine HP. 1D, 2D and 3D simulations have been compared and the results show that the differences of mole fractions of species could reach 75 % between 1D and 2D calculations and 90 % when comparing 2D and 3D calculations.

Date	8 Feb 2018
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	François Garnier (Supervisor)