摘要
采用DPIV技术(粒子图像测速技术)对大板坯连铸结晶器内熔体的流动进行了物理模拟。通过测试分析结晶器内流场,描述了结晶器内熔体流动的基本特征,研究了浸入式水口结构、浸入深度、拉坯速度对结晶器流场的影响。TECPLOT作为后处理软件进行速度向量、流线和各种等值云图的计算与分析,从而揭示金属液流动的规律,以便有目的地控制流动和水口工艺,改善连铸坯的组织性能。结果发现,0°水口与15°水口相比,流体在结晶器上部向上流动的趋势更加强烈,而冲击深度变浅;随着水口浸入深度的增加,液面流速降低,液面附近向上运动的回流范围变得越来越大,向下回流的涡心位置下移。试验表明:液面高度要控制在100～150mm;拉坯速度增加时,结晶器内的流速随之增大,自由表面变得更加不稳定,同时液流对窄面的冲击能量增强。
Physical simulation of melt flow in a mould in continuous casting steel slab was conducted by the digital particle image velocimetry (DPIV) system.Primary character of melt flow in the mould was described by analyzing the flow field.The effects of the submerged nozzle,immersion depth and drawing velocity on the flow field in the mould were investigated.The velocity vector,streamline and various equivalent cloud chart were calculated and analyzed by a commercial software TECPLOT to understand the flow change of liquid metal to control the flow and nozzle structure,improving the microstructure and properties of continuous casting steel slab.The results show that compared by nozzle with 15°,the tendency of flow-up of liquid metal at top of mould is more intense and impacting depth is lower for nozzle with 0°.With increase of submerging depth and decrease of flow velocity,inverse-flow range of up-moving of liquid metal is more broad,which results in the descending of eddy position.The liquid surface height should be controlled to be more than 100 mm.With the increase of drawing velocity,companying with increasing in flow velocity in the mould,surface-free becomes more and unstable,and impacting energy on narrow side is enhanced.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2006年第4期208-211,共4页
Special Casting & Nonferrous Alloys
基金
国家自然科学基金资助项目(50475157)
国家留学回国启动基金项目
