Investigation on In-Flight Heating Process of Cerium Oxide Powders in Radio Frequency Thermal Plasma Considering Thermal Resistance Effect
In-flight heating process of powder particles in radio frequency (RF) thermal plasma have great importance for plasma spraying and spheroidization. The present work investigated this heating process through cerium dioxide (CeO2) powders experimentally and numerically. In experiment, a commercial CeO2 powders (30 μm avg.) injected RF argon plasma and measured temperatures with a DPV-2000 monitor. A model integrating electromagnetic, thermal flow, and heat transfer predictions powder in-flight heating in argon plasma. The melting process of the CeO2 powders with different diameters, the melting time of the powders under thermal resistance effect was analyzed respectively. It was found that the heating process of powder particles have three main stages, among which the heating stage is relevant with a dimensionless parameter, Biot number. When Biot≥0.1, thermal resistance is significant, especially for larger powders. The predicted temperature of the particles at the outlet (1800-2880K) is in good agreement with the experimental measurement results.
Key words: RF thermal plasma, Thermal resistance effect, Heating process, Biot number
Originally published as a SSRN paper (Posted: 26 Aug 2024)
By Yi Su, Ruizhe Liu, Hilal Ahmad, Peng Zhao, Xingyue Jin, Hailong Zhu
