板坯连铸结晶器内流场数值模拟

Numerical Simulation of Flow Field in a Slab Continuous Casting Mold

利用FLUENT软件对1300mm×230mm的板坯结晶器建立了三维稳态数学模型,以流体表面流速和射流冲击深度作为主要参考指标,研究了水口的特性及拉速、水口浸入深度对该水口作用下结晶器内流场的影响.结果表明,A水口作用下具有表面流速大,射流冲击深度小,液面波动大,卷渣的可能性大等特点,且随拉速的增加而逐渐增大;随拉速的增加,结晶器内最大表面流速以0.06m/s的幅度逐渐增大,射流冲击深度呈减小趋势,在150,170和190mm浸入深度下,结晶器液面表面流速最大值分别为0.599,0.518和0.465m/s,射流冲击深度分别为385,410和420mm,随水口浸入深度的增加,结晶器内表面流速逐渐减小,射流冲击深度逐渐增加;在实际生产过程中,使用A水口时应适当降低拉速、增大水口浸入深度;在高拉速的情况下,需用平行水口替换A水口.

A three-dimensional steady-state fluid flow in a 1300 mm×230 mm continuous casting slab mold was simulated using FLUENT to evaluate the performance of a submerged entry nozzle （SEN） and the effects of casting speed and SEN submergence depth on the fluid flow in the mold. The surface velocity and jet impingement depth were calculated and compared. The results show that under the action of nozzle A, the flow field in the mold has a higher surface velocity, smaller jet impingement depth and bigger level fluctuation, slag entrapment happens more easily. And this effect will be enhanced with increasing of casting speed. With increasing of casting speed, the maximum surface velocity in the mold gradually increases at 0.06 m/s, the jet impingement depth tends to be smaller. Under three different submergence depths of 150, 170 and 190 mm, the maximum surface velocity is 0.599, 0.518 and 0.465 m/s, and the impingement depth of the jet 385,410 and 420 ram, respectively. With increasing of the submergence depth of SEN, the surface velocity becomes lower, the jet impingement depth bigger. In the actual production process, a lower casting speed and bigger submergence depth are recommended for nozzle A. For the persuit of high casting speed, a parallel nozzle is needed rather than nozzle A.