摘要随着社会需求的发展,人们对于成品钢质量要求日益增高。为了保证成品钢的质 量,有必要对连铸工艺进行优化。中间包冶金是连铸工艺中一个重要环节,中间包流 场优化是改善钢液质量不可缺少的措施。本课题以单流中间包作为研究对象,研究各 种控流装置及组合对中间包流场分布及 RTD 曲线的影响。选择 L9(34)正交表,通过正 交试验优化出挡坝、挡堰和旋流室的最佳组合方式。实验结果表明:83553
(1) 挡坝、挡堰、旋流室对中间流场有优化作用,但优化作用都不明显。
(2) 确定了单流中间包内挡坝与挡堰的最佳排列顺序为:中间包出口、挡坝、挡 堰、浸入式水口。
(3) 浸入式水口在旋流室的位置为偏右、挡堰与旋流室之间的距离为 20cm、挡 坝与挡堰之间的距离为 30cm 时中间包流场达到最优。此时中间包的死区体积分率 Vd 为 25。06%、实际平均停留时间 Tav 为 424。18s、活塞流体积分率为 25。87%。
(4) 浸入式水口的流量越大,对中间包流场优化越有利。本实验得出的最佳流量 为 3。0m3/h,此时中间包流场达到最优。
毕业论文关键词:单流中间包;水模型实验;死区;控流装置;停留时间
Abstract Tundish metallurgy is an important part of continuous casting process, and the optimization of flow field is an indispensable measure to improve the quality of molten steel。 In this paper, the RTD curve and flow field distribution are studied by using the single strand tundish as the research object, and the influence of the flow control device and the combination on the flow field of tundish is studied。 L9(34) orthogonal table is chosen, and the best combination of the dam, weir and swirl chamber is obtained by orthogonal test analysis。 Experimental results show that:
(1)The dam, the weir and the swirl chamber has an optimum effect on the flow field, but the optimization effect is not obvious。
(2)The best sequence of the weir and the dam is determined: tundish outlet, dam and weir, submerged entry nozzle。
(3)When the position of the submerged nozzle in the swirl chamber is the right, the distance between the baffle and the swirl chamber is 20cm, the distance between the dam and the weir is 30cm, the tundish flow field is optimal。 At this time, volume fraction of the dead zone Vd is 25。06%, actual average residence time Tav is 424。18s and volume fraction of the plug flow is 25。87%。
(4)The greater the flow rate of the submerged nozzle, the more favorable to the optimization of tundish flow field。 The optimal flow rate is 3。0m3/h, and the tundish flow field is optimized at this time。
Key words: Single strand tundish; water model experiment; dead zone; flow control device; residence time
目录
第一章 绪论 1
1。1 研究背景 1
1。2 中间包冶金的发展 2
1。3 中间包冶金的现状 2
1。4 中间包冶金过程物理模拟的动态 3
1。5 中间包水模型实验研究方法 3
1。5。1 停留时间测定 3
1。5。2 流场显示技术 11
1。6 本课题研究目的及内容 11
1。6。1 本课题研究目的 11
1。6。2 本课题研究内容 11
第二章 单流中间包的水模型流场实验 13
2。1 实验原料的选取