Thermal and electrical behavior of silicon rod with varying radius in a 24-rod Siemens reactor considering skin effect and wall emissivity

• Published in: International journal of heat and mass transfer 2017-08, Vol.111, p.1142-1156
• Main Authors: Nie, Zhifeng, Zhou, Yangmin, Deng, Jiushuai, Wen, Shuming, Hou, Yanqing
• Format: Article
• Language: English
• Subjects: Alternating current; Conduction heating; Conductive heat transfer; Convection modes; Current density; Dissipation; Emissivity; Heat transfer; Heating; Mathematical models; Rods; Siemens reactor; Silicon; Skin effect
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2017.04.095

•An Joule heating model using AC is developed for the silicon rods.•The combined effect of the heat dissipation, skin effect and heat conduction is performed.•Temperature profile is analyzed for different rod radii, AC frequencies and wall emissivities.•High frequency current source generates an even temperature profile and obtains higher deposition radius.•The curves of voltage-current in a manufacturing period are obtained. This paper presents an electrical heating model using alternating current (AC) for the silicon rods located in a 24-rod Siemens reactor. In this model, the combined effects of heat dissipation (radiation, convection, and reaction energy), skin effect, and heat conduction owing to Joule effect are examined. The presence of the skin effect, which yields an important radial temperature profile controlled by the heat conduction equation for the rods, has been considered. The present model is validated using industrial current data, and it is observed that the numerical results are in good agreement with them. The influence of the location of the silicon rods, AC frequency, radius of rod, and wall emissivity on the temperature profile and current density has been studied through the application of the developed model. Tailoring the temperature profile of silicon rods and extending the maximum deposition radius has also been performed. Voltage-current curves, which are applied to generate the required heat during the manufacturing period, have also been studied using different AC frequencies and wall emissivities.