Master Thesis: Spray characterization of combustor nozzles in high pressure MILD Combustors with multiphase CFD simulations

Optimization of atomization of liquid biofuels for flameless combustion
As part of a European research project, experimental and numerical studies are currently being carried to characterize and improve the combustion performance of two MILD/ Flameless combustors, which are integral to a micro combined heat/cool power system (CHCP System). The CHCP system is being currently developed for multi-family dwellings not connected to the natural gas grid. It is foreseen that in the future Bioliquid or BioLPG fuels will be supplied through tanks.

To achieve efficient combustion effective atomization is crucial to reach low droplet diameters, which in turns is affects the combustion regime and pollutant emissions. The aim of the current thesis work is the improvement of nozzle spray characteristics and its effects on the combustion zone.

• Analysis of experimental data conducted to ascertain droplet distributions
• Literature research with regards to liquid fuel atomization modelling in MILD/FLOX Combustion
• Physico-chemical modelling of liquid fuel for the numerical studies
• Multiphase simulation of atomization of fuel with adapted geometry for specific conditions
• Possible validation of numerical models with experimental results under ambient conditions
• Extension of modelling conditions to extend to combustion conditions and interaction with hot incoming air

Mechanical Engineering (Maschinenbau), Aerospace Engineering (Luft-und Raumfahrttechnik), Energie- und Umwelttechnik

Prerequisites:

• Good fundamental knowledge of fluid flow physics and preferably also of combustion physics
• Knowledge of multiphase flow is a plus
• Able to work independently and in a scientifically structured manner
• Ability to code and experience with atleast one CFD Solver such as ANSYS Fluent, CFX, Star-CCM+ or CONVERGE
• Experience with Meshing tools such as ICEM-CFD is desired but not a must.

• Support and structured supervision of work
• Possibility to work part time as a student
• Depending on the results, possibility to cowrite a scientific article

Theoretical and numerical simulations

 Earliest joining date: 07.02.2025

4 – 6 months