基于F曲线的多流非对称中间包死区计算模型

为了解决组合模型计算多流非对称中间包不同出口的停留时间分布曲线时出现的体积死区分率为负或结果偏差较大的问题,通过把“脉冲刺激-响应”试验所得的E曲线转换为F曲线,建立了基于F曲线的多流非对称中间包整体死区比例分析模型,并通过比较各流出口F曲线的差异量以及差异量极大值、最大值评价了多流非对称中间包钢液流动一致性。应用该模型对四流非对称中间包流场进行分析,水模型试验结果表明,无控流装置的中间包在3号、4号水口上方存在流动缓慢的区域,中间包钢水更新缓慢,流场不合理。增加挡墙后,中间包钢水流动一致性增强,2号、3号水口流动一致性相近;1号、4号水口流动一致性相近。使用挡墙+挡坝2的组合,各流一致性最好,死区比例最小。

A model for dead volume fraction in multi-strand asymmetric tundish based on F curve

In order to solve the problem of negative dead volume fraction or bigger calculation errors when the combined model is used to calculate the residence time distribution curves of different outlets of multi-strand asymmetric tundish, the E curve obtained from “pulse stimulus-response” tests was transformed into F curve, which could be used to establish an analysis model for dead volume fraction in a multi-strand asymmetric tundish based on F curve. Meanwhile, the flow uniformity of molten steel in the whole multi-strand asymmetric tundish was also evaluated by comparing the flow concentration difference and the local maximum, global maximum difference of F curves between the different strands. This model was used to analyze the flow characteristics of four-strand asymmetric tundishes. The results show there is a slow flow area above the No.3 and No.4 nozzles in tundish without the flow control device, and the molten steel renewal in tundish is slow, and the flow field is unreasonable. With the addition of the retaining wall, the consistency of flow in tundish is enhanced, and the flow consistency of No.2 and No.3 nozzles is similar, and that of No.1 and No.4 nozzles is similar. Using the combination of retaining wall and dam 2, the consistency of each flow is the best and the proportion of dead volume fraction is the smallest.