共查询到19条相似文献,搜索用时 140 毫秒
1.
以国内某钢厂45t钢包为研究对象,在相似原理的基础上建立了钢包吹氩水模型(模型与原型的几何比为1∶2.5),研究了吹氩孔的位置和吹氩流量对钢液混匀特性的影响。实验发现:无论是单孔吹氩还是双孔吹氩都存在一个临界流量,在临界流量时钢液混匀特性最好。其中对于单孔吹氩工艺,吹氩位置在距离钢包底部中心0.5R(钢包底半径)处较合理,模型临界流量为0.35m3/h;对于双孔吹氩工艺,两孔位置在0.5R、角度为45°较理想,模型临界流量为0.40m3/h。工业试验表明,改进后的吹氩方案在降低总氧和夹杂物方面均优于改进前的吹氩方案。 相似文献
2.
3.
以180 t双孔底吹氩钢包为研究对象,对6种钢包底吹氩模式进行数值模拟,并结合现场试验与当前采用的吹氩模式进行对比。研究发现:(1)钢液的混匀时间随吹氩量的增加而减少,吹氩量一定时,差流量吹氩模式对钢液的搅拌强于等流量吹氩模式。(2)不同的钢包底吹氩模式,渣眼形成的位置不同,渣眼面积也不同。总流量一定时,差流量吹氩模式钢液面最大流速大于等流量吹氩模式,易发生钢液卷渣。(3)差流量吹氩模式渣线处渣层厚度的波动大于等流量吹氩模式,且流量差值越大,波动越剧烈。(4)差流量吹氩模式通过“强-弱”流股的配合,进一步强化了钢包底吹氩的钢液精炼效果。工业试验表明,采取等流量吹氩模式(500 L/min—500 L/min),钢中的较大夹杂物的数目明显多于差流量吹氩模式(400 L/min—600 L/min)。 相似文献
4.
5.
6.
以某厂70 t钢包为研究对象,采用数值模拟的方法对比了吹氩量对钢包内不同比表面积和预热温度的废钢熔化行为.结果表明:废钢熔化速度随着比表面积的增加而加快;底吹氩气可显著加速废钢熔化,但随着比表面积的增加吹气的促进效果逐步减弱.有底吹氩时,比表面积为120、130.22和160.81 m2·m–3的废钢中心温度上升速率相较于无底吹氩时分别提高了7.06、6.51和3.73 K·s–1,熔化速率分别增加了0.92、0.88和0.28 cm3·s–1,熔化时间分别缩短了17、15和3 s.板形废钢初始温度由300升到1000 K时,其熔化速度由2.97提高到3.26 cm3·s–1,熔化时间缩短了3 s.底吹氩流量显著影响废钢熔化速度,当氩气流量由100增至200 L·min–1时,比表面积为120、130.22和160.81 m2·m–3的废钢熔化时间分别由44减小到35 ... 相似文献
7.
8.
9.
10.
在相似原理的基础上,以45t直筒型精炼钢包为研究对象,建立1:2.5的水力学物理模拟模型,考察钢包底吹精炼过程中喷吹位置、喷吹量对混匀效果的影响。研究结果表明,随着底吹气量的增大,混匀时间减小,当气体流量超过临界流量90L/min,减小幅度减弱;底吹透气砖布置在距包底中心1/2处时,混匀效果最好。 相似文献
11.
12.
应用欧拉-欧拉模型建立了钢包内钢液流动及混合过程的数学模型,考察了吹气量对中心底吹及偏心底吹钢包内流场及均混时间的影响。计算结果表明,钢包底部四周为流动缓慢区域;吹气量越大,一方面可以降低均混时间,另一方面会导致钢包自由液面的钢液流速增大,从而容易造成卷渣;从缩短混合时间,提高生产效率考虑,偏心底吹更为有利。 相似文献
13.
针对攀钢200t钢包,采用物理模拟与数值模拟相结合的方式,研究了透气砖布置方式和吹氩流量对钢液流动行为的影响规律。结果表明,当两透气砖呈120°布置在距包底中心0.62R(R为包底半径)处时,钢液的平均流速和平均湍动能大,"死区"范围小,混匀时间短,是合理的透气砖布置方式,其临界吹氩流量为27m3/h;与单透气砖相比,双透气砖喷吹的能量利用率高,"死区"范围小,单透气砖的吹氩流量需控制到45m3/h才能达到与双透气砖吹氩流量为27m3/h时相同的搅拌效果。实践证明,研究得到的透气砖布置方式和吹氩流量能保证熔池的搅拌效果,使转炉钢水经吹氩处理后,钢包不同位置温差小于10℃,Δw[C],Δw[Si],Δw[Mn]小于0.03%;在一定的软吹氩流量条件下,吹氩时间大于等于8min,可以使钢中wT[O]小于25×10-6。研究表明,用离散相模型对钢包底吹氩过程进行数值模拟,可以得到与物理模拟试验和生产实践较为吻合的结果。 相似文献
14.
A water model of a typical 150t ladle was designed and constructed to determine the flow characteristics. A kind of organic emulsion was selected to model nonmetallic inclusion particles with the purpose of studying the inclusion removal effect under gas blowing in a teeming ladle. The presented modeling method for inclusion particles in the teeming process is different from those under steady condition. The numerical simulation was performed by using commercial software with the Eulerian‐Eulerian multiphase model applied to a model gas blown through a ladle. The numerical component of this study was conducted aiming at exploring the transient flow characteristics in teeming ladle corresponding to the physical experimental condition. Under the present conditions the authors came to the conclusion that soft gas blowing (2.7~4.0 × 10?6 m3/s) was favourable to float inclusion particles into the slag layer. It is suggested to end the gas blowing when the drainage percentage reaches 50%. 相似文献
15.
钢包吹氩工艺的优化与完善 总被引:7,自引:1,他引:6
重点介绍钢包底吹氩工艺,并对钢包吹氩原理及吹氩工艺过程中的几个关键工艺参数的选取加以分析论述。从而优化工艺参数,提高产品的内在质量。 相似文献
16.
17.
Two cold models were employed to simulate the formation of open‐eyes in a gas stirred ladle. In the first model, water and silicon oils were employed to simulate liquid steel and slag respectively. In the second one, liquid Ga‐In‐Sn alloy was used to simulate liquid steel, while 12% hydrochloric acid simulated the top slag. The experimental results indicated that the gas flow rate, height of the lower liquid and height of the top liquid had a strong impact on the open‐eye size. On the other hand, the viscosity of the top liquid and the interfacial tension between the two liquids had only little effect on the open‐eye size. A semi‐empirical model was developed to describe the size of open‐eye as a function of the heights of the two liquids and the gas flow rate. The two sets of parameters obtained for the water and Ga‐In‐Sn models were very different. Industrial trials were also conducted to examine the applicability of the models. The model developed based on the Ga‐In‐Sn model could well predict the formation of an open‐eye during ladle treatment. The model could be adopted by the industry to estimate the real gas flow rate by measuring the size of the open‐eye online. On the other hand, the mathematical model based on water model experiments was unsatisfactory when applied to the industrial ladle process. 相似文献
18.
蓄热式钢包烘烤的数值模拟 总被引:3,自引:0,他引:3
为了对钢包的烘烤温度进行在线预测,笔者耦合了流体流动、燃烧和换热过程,建立了多入口、多出口的三维非稳态钢包烘烤数学模型。利用计算流体力学软件CFX4.3,采用有限差分方法和修正的速度一压力耦合算法SIMPLEC,计算了某厂蓄热式钢包内衬的温度分布,重点分析了不同气体预热温度下钢包内衬温度的变化规律,并进行了实验验证。结果表明,采用助燃空气一煤气双预热的蓄热式燃烧技术能够有效地提高钢包的烘烤速度和加热均匀性;气体预热温度越高,包衬终点温度越高,温度均匀性也越好。计算结果与实验及工程现象基本吻合,证明该模型对指导现场生产具有重要意义。 相似文献