Skip to Main content Skip to Navigation
Theses

Solutions architecturées par fabrication additive pour refroidissement de parois de chambres de combustion

Abstract : Combustion chamber walls are perforated with holes so that a cooling air flow can be injected through them. The wall is cooled by convection and an insulating film is created on the hot surface (film cooling). This PhD thesis aims to use the possibilities of additive manufacturing to provide new architectured solutions that could enhance the internal heat exchanges, and lead to a higher cooling effectiveness.The first approach is to develop new designs of multiperforated walls by Electron Beam Melting (EBM) and Selective Laser Melting (SLM) used at the resolution limits of the processes. They are characterized by microscopy, X-ray tomography and permeability tests. Some aerothermal simulations help understanding the effects of these new designs on the flow and on heat exchanges. These results lead to a geometry adaptation.The second approach is to simultaneously manufacture an architectured part with dense and porous zones by EBM. Thanks to image analysis combined with large field EBSD, it is possible to investigate the mechanisms leading to the porous zones and to link them to permeability and porosity. The film cooling effect could be favoured by the orientation of pores towards the cooling flow. Therefore, a new powder-based manufacturing process named Magnetic Freezing, where metallic powders organize into an oriented structure thanks to a magnetic field, is developed.The various solutions studied during this thesis are tested on an aerothermal bench. They all show a more efficient and homogeneous cooling than the industrial reference. Some first tests on one of the selected solutions are performed on a combustion bench. This lighter and more permeable structure proves to be a solution as efficient as the industrial reference at a given flow rate. It should therefore be a more efficient solution for a given overpressure.
Complete list of metadatas

Cited literature [87 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01737591
Contributor : Abes Star :  Contact
Submitted on : Monday, March 19, 2018 - 3:46:08 PM
Last modification on : Wednesday, October 7, 2020 - 1:16:03 PM
Long-term archiving on: : Tuesday, September 11, 2018 - 7:47:03 AM

File

LAMBERT_2017_archivage.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01737591, version 1

Collections

Citation

Océane Lambert. Solutions architecturées par fabrication additive pour refroidissement de parois de chambres de combustion. Matériaux et structures en mécanique [physics.class-ph]. Université Grenoble Alpes, 2017. Français. ⟨NNT : 2017GREAI048⟩. ⟨tel-01737591⟩

Share

Metrics

Record views

985

Files downloads

1213