Abstract: The paper investigates the effect of fiber morphology on the formation mechanism of carbon nanotube fibers in a vertical reactor with a side inlet by chemical vapor deposition (CVD). According to the established fiber/gas two-phase flow model, the gas flow field is solved by numerical simulation to obtain the gas velocity, and then the fiber movement in the gas flow field is solved by numerical simulation. The simulation results showed that the gas velocity in the reactor with a side inlet fluctuated a lot, and there were obvious vortex regions, especially in the front section of the reactor. After entering the heating section, the vortex became smaller and longer. In the end, the gas velocity became stable; and there were reflux and vortex in the near wall region. The fiber movement in this reactor fluctuated obviously and elongated at the same time. The fiber movement obtained by the simulation is conducive to the formation of a carbon nanotube fiber “hose” structure and the densification of carbon nanotube fiber.

Key words: chemical vapor deposition; gas flow field; fiber model; numerical simulation; fiber movement