Numerical Simulation Of Cathode Busbar Fusing Process In Aluminum Reduction Cells

The accident of cathode busbar fusion could cause great loss in economy to the aluminum reduction factory. On the basis of collecting the information and material sufficiently, the reason of busbar fusion was concluded initially. Then using the commercial software ANSYS, taking the busbar system as subject, three-dimension thermo-electric model of normal busbar, actual busbar with deficiency and conduction system of three cells was developed to research the busbar thermo-electric balance process in the whole accident.The main innovations and conclusions in this dissertation are summarized as follows:(1) The physical and mathematical model of cathode busbar were developed in ANSYS and the boundary conditions were determined. According to the measured data of cell in the same series and case, the heat transfer coefficient between busbar and surroundings was determined and the busbar convection formula was modified;(2) The thermo-electric field of normal cathode busbar was calculated, its results show that the busbar voltage (558mV) approaches to the measured data of cell in the same series (560mV); The voltage gradient of busbar in the middle part near to the output end is a little greater than any other positions, which accords with the measured results. So the computational model and method was proved to be reliable and the modified heat transfer coefficient was also reasonable;(3) The thermo-electric balance process of the actual busbar with hole was studied, the effect of busbar current, heat transfer coefficient, environment temperature and current capacity on the busbar balanced voltage and the maximum temperature was also researched. The conclusions is that compared to the heat transfer coefficient and the environment temperature, the influence of busbar current and the current capacity on balanced voltage and the maximum temperature is more obvious;(4) The whole accident process can be divided into two stages according to the voltage change recorded and the thermo-electric balance process of each stage was simulated, the results are in accord with the measured data. The electromagnetic force of busbar at that time was also estimated. By analyzing synthetically, the reason of busbar fusion were found out and the problem was settled, which can provide the guidance for late safety production.