Combustion and chemical reactions
This module focused on the physics and numerical modeling of combustion, combining chemical kinetics, thermodynamics, species transport, and turbulent reacting flows. It built from fundamental reaction chemistry toward advanced industrial combustion simulations, using both CHEMKIN and Ansys Fluent to study how chemical reactions interact with fluid dynamics and heat transfer.
The coursework progressed through increasingly complex combustion regimes:
Chemical kinetics and equilibrium: the first assignments focused on reaction mechanisms, stoichiometry, thermodynamic properties, and equilibrium chemistry. Using CHEMKIN, I analyzed methane and hydrogen combustion, reaction rates across large temperature ranges, diffusion coefficients, and equilibrium species composition. This established a strong understanding of how temperature, mixture composition, and chemical pathways influence combustion behavior.
Laminar premixed and non-premixed flames: the next stage introduced flame structure, ignition behavior, flame speed, and species evolution in controlled laminar combustion. Simulations explored how mixture fraction, equivalence ratio, and reaction progress affect temperature and product formation.
Turbulent combustion modeling: later assignments moved into practical CFD combustion models, including premixed, partially premixed, and non-premixed turbulent flames. Different combustion closures were compared, with emphasis on turbulence–chemistry interaction and the trade-offs between accuracy and computational cost.
Pollutant formation: dedicated studies investigated NOx and CO formation, examining how temperature peaks, oxygen availability, and residence time influence pollutant generation. These exercises showed how emissions are tightly coupled to combustion efficiency and flame structure.
Multiphase combustion: one of the most advanced projects involved coal combustion, combining turbulence, radiation, discrete particle tracking, devolatilization, and char burnout. This highlighted the complexity of industrial-scale combustion where solid particles, gas-phase chemistry, and heat transfer all interact simultaneously.
Final project – Piloted methane jet flame: the capstone simulation modeled a canonical turbulent methane-air flame from the TNF workshop benchmark, comparing numerical predictions against reference data. This project brought together the full CFD workflow: geometry setup, mesh design, boundary condition selection, turbulence modeling, combustion model selection, and detailed post-processing of velocity, temperature, and species fields.
Throughout the module, I saw how combustion modeling demands balancing physical realism with numerical tractability. Small changes in reaction mechanisms, turbulence models, or boundary conditions could significantly alter flame structure, temperature distribution, and emissions predictions.
This module brought together nearly every major topic from the CFD degree into a single multiphysics framework. It gave me practical experience in modeling reacting flows ranging from idealized flames to industrial combustion systems, while strengthening my ability to interpret complex interactions between chemistry, transport phenomena, turbulence, and heat transfer.