机构地区: 华南理工大学机械与汽车工程学院
出 处: 《华南理工大学学报(自然科学版)》 2015年第11期67-74,共8页
摘 要: 基于二维非稳态传热-多相流耦合模型和三维非稳态单辊结晶器传热模型,结合生产数据,对平流铸造Fe_(78)Si_9B_(13)时熔潭形成过程中的流动、传热现象以及结晶器内的传热特征进行了研究.结果表明:在文中工艺条件下,熔潭稳定形成后,其上游弯月面呈C形,下游弯月面呈带波纹的斜坡状;结晶器达到热平衡状态的时间为20 s;高温熔体对结晶器冲击后,会在距表面0.0004 m范围内形成一个热冲击区,该区域表面中心最高温度可达513.5 K;与径向热膨胀相比,结晶器周向热膨胀对实际总膨胀量的贡献更大,约为96%. On the basis of two models,namely,the developed coupled model of two-dimensional transient heat transfer and multiphase flow and the model of three-dimensional transient heat transfer of single-roller crystallizers,the fluid flow and heat transfer behaviors during the puddle forming precess of the planar flow casting( PFC) of Fe_(78)Si_9B_(13) as well as the heat transfer characteristics of rollers are investigated according to the production data.The results show that( 1) under a given casting condition,the upstream and downstream meniscuses of the formed puddle are respectively in a crescent shape and in a slope shape with ripple;( 2) the time for the crystallizer to reach a quasi-thermal equilibrium state is 20 s;( 3) the impact of high temperature melts on the crystallizer causes an melt impact region of a depth of 0. 000 4 m to form,where the maximum temperature in the center of crystallizer surface is about 513. 5 K; and( 4) in comparison with the radial thermal expansion,the circumferential thermal expansion of crystallizer plays a more important role in the actual total expansion,which accounts for 96%.
领 域: [冶金工程]