(中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 針對(duì)鋁電解槽內(nèi)熔體旋轉(zhuǎn)流動(dòng)的特點(diǎn)，提出使用渦量和旋轉(zhuǎn)強(qiáng)度來(lái)對(duì)其渦結(jié)構(gòu)進(jìn)行定量解析，并以某300 kA槽電解質(zhì)流場(chǎng)為研究對(duì)象，使用CFX12軟件平臺(tái)進(jìn)行數(shù)值模擬。結(jié)果表明：極間水平截面和陽(yáng)極間縫垂直截面的旋轉(zhuǎn)強(qiáng)度最大值分別為1.611和1.961 s−1，其絕對(duì)渦量最大值分別為4.002和3.391 s−1；陽(yáng)極氣泡的攪動(dòng)使陽(yáng)極周?chē)娊赓|(zhì)中成對(duì)出現(xiàn)反向?qū)ΨQ(chēng)小渦；而電磁力的不均勻性導(dǎo)致部分陽(yáng)極底部出現(xiàn)不對(duì)稱(chēng)大渦；陽(yáng)極中縫和間縫相交位置的絕對(duì)渦量超過(guò)4 s−1，在該位置布置下料點(diǎn)有利于氧化鋁的分散。故運(yùn)用渦分析法能得到更為豐富和精確的流場(chǎng)信息，為槽結(jié)構(gòu)的設(shè)計(jì)提供理論指導(dǎo)。
關(guān)鍵字: 鋁電解槽；電解質(zhì)；渦；渦量；旋轉(zhuǎn)強(qiáng)度；數(shù)值模擬
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:In view of the characteristics of the rotation flow of the melt in aluminum reduction cells, the methods of vorticity and swirling strength were introduced to analyze the vortical structures of aluminum reduction cells quantitatively. Based on the software CFX12, the electrolyte flow field in a 300 kA cell was numerically simulated. The results show that the maximum swirling strengths on the interpolar horizontal plane and the vertical cross-section plane of the anode gap are 1.611 and 1.961 s−1 respectively, and the maximum absolute vorticities are 4.002 and 3.391 s−1, respectively. Small vortexes occur as reverse symmetrical pairs around the anode because of the stirring of anode gas, while large asymmetric vortexes are caused under some anodes by the nonuniformity of electromagnetic forces (EMFs). The alumina feeding points should be set at the intersection position of center channel and anode slots to achieve the best mixing effect of alumina, where the absolute vorticity is greater than 4 s−1. Thus, the above method can provide more flow field information with higher precision and theoretical guidance for the structural design of the cell.
Key words: aluminum reduction cell; electrolyte; vortex; vorticity; swirling strength; numerical simulation
