Abstract Submitted to the    NANOTUBE'04 Conference:

Effect of forced convective heat transfer on the formation of carbon nanoparticles (CNPs) synthesized by a simple method of submerged arc discharge was investigated experimentally and theoretically. Introduction of the water flow rate of 0 - 3.2 dm3/min (0 – 7.1 m/s) could remarkably affect the arc discharging, which in turn gave rise to the change of CNPs’ properties and production rate. With TEM, Raman and DLS analyses, it was proven that the mixtures of CNPs consisting of polyhedral particles and multi-walled carbon nanotubes. With the water flow rate of 1.36 dm3/min, the highest yield and production rate of CNP-rich product could be obtained at 48.5 % and 9.32 g/h, respectively. An increase in water flow rate gave rise to faster heat transfer rate resulting in the decreasing average hydrodynamic diameter of CNPs produced. It could be implied that a further increase in water flow and heat removal leads to accelerated rate of formation of nano-onions or nano-polyhedral particles instead of CNTs. Based on the experimental results, the postulated mechanism of formation of CNPs in convective flow field was proposed.