Design of an Atmospheric Burner for Generating Representative Jet Engine Soot in Contrail Formation Studies

Abstract

This thesis presents the design of an atmospheric-pressure burner for generating soot representative of jet engine exhaust to be used in contrail formation studies. The motivation comes from the need to better understand the role of soot as ice-nucleating particles in contrail formation and its climate impact through radiative forcing in the atmosphere. Existing laboratory burners either fail to produce representative soot or lack well-defined boundary conditions for simulation. The primary objective of this project was to design a burner that produces a controlled and repeatable flow field while being simulation-friendly. Furthermore, it required compatibility with laser-based diagnostics and soot sampling for transmission electron spectroscopy (TEM) analysis. A flame spray pyrolysis (FSP) burner was designed and iteratively evaluated based on comparisons with burners reported in the literature and computational fluid dynamics (CFD) analysis using ANSYS Fluent. The final design integrates favorable features from burners that were capable of generating aircraft-like soot and those that were simulation-friendly. The burner design was then evaluated on its ability to achieve the required hydrodynamic flow field for representative jet engine soot formation, as well as its simulation-friendliness, compatibility with the laboratory experimental setup, and compliance with safety, machining, and usability constraints. Results indicate that the final burner design successfully met these objectives. It is capable of producing suitable conditions for generating aircraft-like soot while having well-defined boundary conditions. This project establishes a foundation for future in-situ contrail formation studies using representative jet engine soot made within a controlled laboratory environment.