Numerical modelling of Chemical Vapor Infiltration (CVI) process for densification of carbon disk brakes for high-performance applications

 

Abstract

MSc Thesis CVI Disks

Carbon disk brakes are mainly produced using the Chemical Vapor Infiltration (CVI) process. CVI is a process in which a gaseous stream (typically methane) flows over and around a porous carbon matrix at high temperature (~1100 °C) and low pressure (~0.10 atm). Thanks to the chemical interactions between the gaseous stream and the solid substrate surface, carbon deposition in the preform structure occurs. Over time, the preforms fill in and become denser, and ultimately form the desired carbon composite. In particular, the carbon disk brakes are typically produced by stacking a series of low-density carbon preforms within a reactor with electrically heated graphite walls. After a sufficiently long time (~100 h), carbon disk brakes of appropriate densities are removed from the reactor for further processing.
The aim of this thesis is to explore new geometrical configurations and alternative operating conditions to optimize the densification process of carbon disk brakes for high-performance applications. The starting point is represented by an existing industrial reactor able to process ~18 preforms per time, for which experimental data are available. Numerical tools already available in the CRECK Modeling Lab will be used to perform the study. In particular, the laminarSMOKE code will be adopted for carrying out the CFD simulations of the reactor, while the CVISMOKE++ code for performing the densification simulations of individual disks. The optimization will especially aim at finding the geometrical and operating conditions able to maximize the homogeneity of the densification process and minimize the differences among the disks in the reactor.

 

Details

Duration: 12 months

Experimental activities: no

Skills: basics of transport phenomena and numerical methods

Advisor: Alberto Cuoci

People involved: Alessio FrassoldatiTiziano Faravelli