面向风电消纳的铝电解槽瞬态温度场的波动特性研究

针对铝电解系列消纳风电过程中电流波动对热场作用过程不明确的现状,应用电热场瞬态强耦合模型对某420kA大型铝电解槽在一个完整消纳周期内的热场进行研究。分别针对消纳电流为设计电流的2%、5%和10%三种情况,消纳持续周期为2h,恢复周期为6h,计算铝电解槽温度场的瞬态变化特性。结果表明,槽内各区域的温度均随着强化幅度的增加而增加,变化最大的区域为熔体区;越靠近熔体区域的部分,温度的变化幅度越大;而除导杆、钢爪外,越靠近槽壳表面部分,温度的变化幅度越小。在电流恢复至正常值期间,电解槽温度下降速度缓慢,需要比较长的时间才能恢复到正常值,故铝电解槽电流波动幅度不宜太大。

Study on Fluctuation Characteristics of Instantaneous Temperature Field in Aluminum Electrolysis Pot for Wind Power Accommodation

To solve the unclear effect of current fluctuation on temperature field during accommodating wind power by electrolysis pot, transient strongly coupled thermo-electric model was built to study thermal field of a 420 kA large-scale aluminum electrolysis pot during a complete accommodation cycle. With two-hour accommodation cycle and six-hour recovery cycle, transient variation characteristics of thermal field were calculated for different accommodation current, namely 2%, 5% and 10% of the design current. The results show that temperature of each region in pot rises with increase of enhancement amplitude, and the maximum temperature change occurs in melt zone. The region in pot closer to melt zone shows bigger change of temperature while the region closer to shell has smaller change of temperature except for aluminum rod and steel claw. Temperature of pot drops very slowly during a relatively long period when current return to design value. Therefore, the current fluctuation amplitude in aluminum electrolysis pot should not be too large.