Modeling reactive rarefied flows in Chemical Vapor Infiltration using Direct Simulation Monte Carlo

Chemical Vapor Infiltration (CVI) is a key method for fabricating silicon carbide (SiC) matrix composites. Gas-phase precursors flow into a porous fiber, react, and deposit to form the ceramic matrix. Deposition quality and rate are strongly influenced by surface reactions, depending on temperature, gas flow, and reactor pressure. This study applies a computational model to better understand rarefied gas behavior and surface chemistry during CVI. We use the Direct Simulation Monte Carlo method to simulate gas flow and chemical reactions around the fibers. Simulations span Knudsen numbers 0.001–20 and temperatures 1000–1600 K (near‑continuum to free‑molecular). As rarefaction increases, deposition rate decreases, yet temperature remains significant. In forced‑flow CVI, deposition becomes uneven: the fiber's inlet side grows more, the opposite side less. To improve gas‑phase chemistry accuracy, we adapt a Quantum‑Kinetic model for methyltrichlorosilane and chlorine reactions. Overall, it clarifies how rarefied gas dynamics and activation energy control CVI.

Grantor dc:publisher

University of Tennessee at Chattanooga

Author dc:creator

• EK, Ege C

Contributors dc:contributor

• Barisik, Murat
• Sreenivas, Kidambi; Ranjan, Reetesh
• College of Engineering and Computer Science

• Chemical vapor deposition
• Monte Carlo method
• Rarefied gas dynamics
• Silicon carbide--Thermal properties
• Surface chemistry--Mathematical models

Licence

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language

English, eng

Repository record dc:identifier

https://scholar.utc.edu/theses/1021

OAI identifier oai:identifier

oai:scholar.utc.edu:theses-2207