Optimization of Flame Parameters and Synthesis Chamber Diameter Toward Carbon Nanotubes Growth Within Quasi-Pyrolysis Environment Through CFD Simulation and Taguchi Method

Flame synthesis utilizing a quasi-pyrolysis chamber represents a recent advancement in the scalable production of carbon nanotubes (CNTs). However, limited research has been conducted to optimize the parameters influencing CNT growth within such chambers. This study aims to investigate the effects of fuel and oxidizer flow rates on the spatial distribution of CNT growth in a quasi-pyrolysis synthesis chamber with varying diameters. A computational fluid dynamics (CFD) model, developed at flame scale, was used in conjunction with a growth rate model (GRM) to predict CNT length and growth regions along both radial and vertical axes within the synthesis chamber above a methane diffusion flame. The Taguchi method was employed to identify the most influential parameters for CNT growth and their optimal levels. Interestingly, the analysis revealed that the optimum conditions included a high fuel flow rate, which increased CNT production costs. To achieve a more cost-effective solution, the fuel flow rate was reduced while maintaining the optimized levels of oxidizer flow rate and chamber diameter. The results show the possibility to enhance the CNT growth up to 2600% by optimizing the flame parameters accordingly.