A theoretical investigation of fluid flow,heat transfer and solidification(solidification transfer phenomena,STP)was presented which coupled with direct-current(DC)magnetic fields in a high-speed strip-casting metal d...A theoretical investigation of fluid flow,heat transfer and solidification(solidification transfer phenomena,STP)was presented which coupled with direct-current(DC)magnetic fields in a high-speed strip-casting metal delivery system.The bidirectional interaction between the STP and DC magnetic fields was simplified as a unilateral one,and the fully coupled solidification transport equations were numerically solved by the finite volume method(FVM).While the magnetic field contours for a localized DC magnetic field were calculated by software ANSYS and then incorporated into a three-dimensional(3-D)steady model of the liquid cavity in the mold by means of indirect coupling.A new FVM-based direct-SIMPLE algorithm was adopted to solve the iterations of pressure-velocity(P-V).The braking effects of DC magnetic fields with various configurations were evaluated and compared with those without static magnetic field(SMF).The results show that 0.6 T magnetic field with combination configuration contributes to forming an isokinetic feeding of melt,the re-circulation zone is shifted towards the back wall of reservoir,and the velocity difference on the direction of height decreases from 0.1 m/s to 0.Furthermore,the thickness of solidified skull increases uniformly from 0.45 mm to 1.36 mm on the chilled substrate(belt)near the exit.展开更多
A mercury model has been developed to investigate the influences of Electromagnetic Mold Brake Ruler(EMBr-Ruler) and Flow Control Mold(FC Mold) on metal flow in slab continuous casting mold with the practical casting ...A mercury model has been developed to investigate the influences of Electromagnetic Mold Brake Ruler(EMBr-Ruler) and Flow Control Mold(FC Mold) on metal flow in slab continuous casting mold with the practical casting speed 1.0,1.3 and 2.0 m/min respectively.FC-Mold can efficiently repress the surface flow and its fluctuation.The expanding space of the jets is compressed by EMBr-Ruler and FC-Mold respectively,then the 'flow passage' where the vertical velocity of flow increases sharply is developed near the narrow wall with EMBr-Ruler and FC-Mold.It is bad for the development of the plug like flow.Only the nozzle ports are placed in the braking magnetic field region and the casting speed is suitable,EMBr can be beneficial to the formation of the plug like flow.The flow regime is improved with FC Mold when the casting speed is high(2.0 m/min),but EMBr can improve the flow field with medium casting speed(1.3 m/min),but when the casting speed is low(1.0 m/min),the effects of two types of EMBr are both unsatisfactory.展开更多
Three-dimensional mathematical model coupling of the molten steel flow and heat transfer in the slab continuous casting mold and secondary cooling zone is established to describe molten steel flow and heat transfer ph...Three-dimensional mathematical model coupling of the molten steel flow and heat transfer in the slab continuous casting mold and secondary cooling zone is established to describe molten steel flow and heat transfer phenomena in the slab continuous casting mold with EMBR.The computational model is applied to investigate the flow field and temperature field in slab mold contrast with and without a constant EMBR,which strength measured at a steel plant.The study shows that The EMBR has not changed the mold steel flow field characteristic.But it has reduced the intensity of the upper and downer recirculation in the mold,reduced the speed of the upper recirculation zone,increase the free surface temperature which is compared to the state without EMBR.展开更多
对梅钢2#连铸机采用的FC-Mold(Flow Control Mold)全幅二段电磁制动器对钢中非金属夹杂物的影响进行了研究。结果表明,采用电磁制动后,铸坯中心的夹杂物总个数少于未采用电磁制动的铸坯,而前者边部的夹杂物个数则是后者的2.06倍;铸坯中...对梅钢2#连铸机采用的FC-Mold(Flow Control Mold)全幅二段电磁制动器对钢中非金属夹杂物的影响进行了研究。结果表明,采用电磁制动后,铸坯中心的夹杂物总个数少于未采用电磁制动的铸坯,而前者边部的夹杂物个数则是后者的2.06倍;铸坯中心和边部的夹杂物平均直径和平均面积均有所减小,铸坯中心的平均面积减小量达到8.44μm2。钢中的夹杂物主要为直径全部小于20μm的Al2O3、MnS和CaS夹杂物,还有少量含K、Na的夹杂物。未采用电磁制动的铸坯中含K、Na夹杂物的数量明显多于采用电磁制动的铸坯。采用电磁制动明显降低结晶器液面的波动幅度,这有助于减少卷渣几率。电磁制动使用技术还有待于进一步优化研究。展开更多
对梅钢2号连铸机采用的FC-Mold（Flow Control Mold）全幅2段电磁制动器使用效果进行了研究。结果表明，随着线圈电流强度的增加，磁场强度增大，结晶器内流动情况随之发生变化。当下部线圈电流为800～850A时，结晶器下部磁场强度在0．3...对梅钢2号连铸机采用的FC-Mold（Flow Control Mold）全幅2段电磁制动器使用效果进行了研究。结果表明，随着线圈电流强度的增加，磁场强度增大，结晶器内流动情况随之发生变化。当下部线圈电流为800～850A时，结晶器下部磁场强度在0．35～0．45T左右。上部线圈电流从100A增加到400A时，结晶器上部磁场强度随电流强度增加从0．2T增加到0．3T以上。采用电磁制动技术后，结晶器液面波动幅度明显降低，结晶器内钢液温度约上升10℃左右，钢中非金属夹杂物数量较少且尺寸较小，未发现直径大于20μm的夹杂物。但采用电磁制动后仍发生了卷渣现象，该技术还有待于进一步优化研究。展开更多
基金Projects(51071062,51271068,51274077)supported by the National Natural Science Foundation of ChinaProject(2011CB605504)supported by the National Basic Research Program(973 Program)of China
文摘A theoretical investigation of fluid flow,heat transfer and solidification(solidification transfer phenomena,STP)was presented which coupled with direct-current(DC)magnetic fields in a high-speed strip-casting metal delivery system.The bidirectional interaction between the STP and DC magnetic fields was simplified as a unilateral one,and the fully coupled solidification transport equations were numerically solved by the finite volume method(FVM).While the magnetic field contours for a localized DC magnetic field were calculated by software ANSYS and then incorporated into a three-dimensional(3-D)steady model of the liquid cavity in the mold by means of indirect coupling.A new FVM-based direct-SIMPLE algorithm was adopted to solve the iterations of pressure-velocity(P-V).The braking effects of DC magnetic fields with various configurations were evaluated and compared with those without static magnetic field(SMF).The results show that 0.6 T magnetic field with combination configuration contributes to forming an isokinetic feeding of melt,the re-circulation zone is shifted towards the back wall of reservoir,and the velocity difference on the direction of height decreases from 0.1 m/s to 0.Furthermore,the thickness of solidified skull increases uniformly from 0.45 mm to 1.36 mm on the chilled substrate(belt)near the exit.
基金Item Sponsored by National Natural Science Foundation of China[No.50674066]
文摘A mercury model has been developed to investigate the influences of Electromagnetic Mold Brake Ruler(EMBr-Ruler) and Flow Control Mold(FC Mold) on metal flow in slab continuous casting mold with the practical casting speed 1.0,1.3 and 2.0 m/min respectively.FC-Mold can efficiently repress the surface flow and its fluctuation.The expanding space of the jets is compressed by EMBr-Ruler and FC-Mold respectively,then the 'flow passage' where the vertical velocity of flow increases sharply is developed near the narrow wall with EMBr-Ruler and FC-Mold.It is bad for the development of the plug like flow.Only the nozzle ports are placed in the braking magnetic field region and the casting speed is suitable,EMBr can be beneficial to the formation of the plug like flow.The flow regime is improved with FC Mold when the casting speed is high(2.0 m/min),but EMBr can improve the flow field with medium casting speed(1.3 m/min),but when the casting speed is low(1.0 m/min),the effects of two types of EMBr are both unsatisfactory.
基金Item Sponsored by National Natural Science Foundation of China(51004001)
文摘Three-dimensional mathematical model coupling of the molten steel flow and heat transfer in the slab continuous casting mold and secondary cooling zone is established to describe molten steel flow and heat transfer phenomena in the slab continuous casting mold with EMBR.The computational model is applied to investigate the flow field and temperature field in slab mold contrast with and without a constant EMBR,which strength measured at a steel plant.The study shows that The EMBR has not changed the mold steel flow field characteristic.But it has reduced the intensity of the upper and downer recirculation in the mold,reduced the speed of the upper recirculation zone,increase the free surface temperature which is compared to the state without EMBR.
文摘对梅钢2#连铸机采用的FC-Mold(Flow Control Mold)全幅二段电磁制动器对钢中非金属夹杂物的影响进行了研究。结果表明,采用电磁制动后,铸坯中心的夹杂物总个数少于未采用电磁制动的铸坯,而前者边部的夹杂物个数则是后者的2.06倍;铸坯中心和边部的夹杂物平均直径和平均面积均有所减小,铸坯中心的平均面积减小量达到8.44μm2。钢中的夹杂物主要为直径全部小于20μm的Al2O3、MnS和CaS夹杂物,还有少量含K、Na的夹杂物。未采用电磁制动的铸坯中含K、Na夹杂物的数量明显多于采用电磁制动的铸坯。采用电磁制动明显降低结晶器液面的波动幅度,这有助于减少卷渣几率。电磁制动使用技术还有待于进一步优化研究。
文摘对梅钢2号连铸机采用的FC-Mold（Flow Control Mold）全幅2段电磁制动器使用效果进行了研究。结果表明，随着线圈电流强度的增加，磁场强度增大，结晶器内流动情况随之发生变化。当下部线圈电流为800～850A时，结晶器下部磁场强度在0．35～0．45T左右。上部线圈电流从100A增加到400A时，结晶器上部磁场强度随电流强度增加从0．2T增加到0．3T以上。采用电磁制动技术后，结晶器液面波动幅度明显降低，结晶器内钢液温度约上升10℃左右，钢中非金属夹杂物数量较少且尺寸较小，未发现直径大于20μm的夹杂物。但采用电磁制动后仍发生了卷渣现象，该技术还有待于进一步优化研究。
