Reference : UPR3021-CHRCHA-003
Workplace : ORLEANS
Date of publication : Thursday, July 28, 2022
Scientific Responsible name : Fabien HALTER, Christian CHAUVEAU, Stany GALLIER
Type of Contract : PhD Student contract / Thesis offer
Contract Period : 36 months
Start date of the thesis : 1 October 2022
Proportion of work : Full time
Remuneration : 2 135,00 € gross monthly
Description of the thesis topic
ArianeGroup is the European leader in access to space, through its launcher systems and civil and military space applications. ArianeGroup notably designs and develops solid propellants which are used in military and space propulsion (for example Ariane 5 and Ariane 6) and largely provide launcher thrust. These solid propellants contain approximately 20% of aluminum particles, the combustion of which must be better known in order to better predict engine performance..
In the context of new propellants as well as new engines, studies are currently being carried out to better understand and predict the combustion time of aluminum particles. These particles, initially present in the propellant, burn in the combustion chamber and greatly contribute to engine performance. This burning time plays an important role and can have an impact, especially on performance if the burning time is greater than the residence time in the chamber. The combustion of aluminum remains a complex phenomenon and the main objective of this thesis is to experimentally characterize the combustion of aluminum particles in a given oxidizing atmosphere.
The exploitation of the acquired data will contribute to a better understanding of the combustion physics of metal particles and will provide useful input data for the development of future engines.
The works are experimental and numerical.
The experimental part will be carried out at the CNRS ICARE laboratory in Orléans. An experimental system (electrostatic levitator) allowing the characterization of the combustion of an isolated particle will be made available [1-4]. The characterization will consist of direct visualization by means of an ultra-fast camera equipped with a microscopy objective, temperature measurement by two-color pyrometry (1 dimension and 2 dimensions), identification of the excited species present in the reaction zone by spectrometry.
Alternative metals, other than aluminum, may also be tested.
In parallel, it is planned to use the direct numerical simulation of the combustion of metal particles in order to compare the measurements acquired with the current models in order to improve them. The simulation is based on an internal fluid mechanics code, available from Ariane Group, which includes a detailed kinetic description of the gas phase. There are no developments planned, but mainly a use of the computer code to help understand the phenomena. Depending on the results obtained, some improvements (particularly on the kinetics) may however be proposed.
Engineer or Master's degree with skills in combustion and fluid mechanics and a particular interest in experimental work.
The work will be supervised by :
- Christian Chauveau and Fabien Halter at CNRS-ICARE (Orléans, 45)
- Stany GALLIER at Ariane Group (Centre de Recherches du Bouchet, Vert-le-Petit, 91).
The work will be carried out on these two sites (Orléans for the experimental aspects and Vert le Petit for the simulations).
Located on the CNRS campus in Orléans, the PhD student will join the Combustion & Turbulence team of the Institute of Combustion, Aerothermics, Reactivity and Environment (ICARE), which counts about 80 people.
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