通过水模型试验和数值模拟,研究了不同湍流控制器下两流非对称中间包内流体流动特性。数值模拟结果表明:湍流控制器几何结构对两流非对称中间包流体流动特性有明显影响。圆形湍流控制器内流场涡心靠近底部,出口处流体流速垂直向上;中间包流场涡心靠近长水口,涡心高度与挡墙高度基本相同,中间包表面波动大,容易发生卷渣现象。非对称长方形湍流控制器底部为不对称波浪形,流场涡心靠近出口,流体以一定角度从湍流控制器出口流出;其右侧出口面积大于左侧,水口右侧流体流量大于左侧;由于增大了出口面积,出口处流体速度减小,中间包表面平稳。水模型结果表明采用非对称湍流控制器中间包两流之间的平均停留时间差比圆形湍流控制器中间包减少1/4,算术平均值增加5.3%,说明非对称湍流控制器增强了中间包去除夹杂物能力且能有效缩小两流之间流体流动的差异。
Water modeling and the numerical simulation were applied to study the fluid flow in a two-strand asymmetric tundish. Mathematical simulation results showed that the geometric structure of turbulence inhibitor is a key factor to affect the fluid flow in the tow-strand asymmetric tundish. In the case of the circular turbulence inhibitor, the vortex center of flow field is near the bottom of the turbulence inhibitor, and the fluid flows vertically at the exit the of the turbulence inhibitor. The vortex is near the shroud, and the vortex center has the same height as the dam, so there is greater surface vibration, and sometimes slag entrapment occurs. The bottom of asymmetric square turbulence inhibitor has the wave form, and the vortex center is near the exit of the turbulence inhibitor, and the fluid flow obliquely at the exit the of the turbulence inhibitor. Because the exit area at the right side of the turbulence inhibitor is greater than that at the left side, the fluid flow rate at the right side is greater than that at the left side. And the larger the exit area of the turbulence inhibitor, the less the exit velocity of the fluid, and the more stable the free surface of the tundish. Water modeling showed that the difference of the average residue time between two strands in the case of asymmetric turbulence inhibitor is only 3/4 in the case of circular turbulence inhibitor, and thearithmetic mean of the average residue time increase 5.3 percent. All these facts indicated the asymmetric turbulence inhibitor can get rid of the inclusions effectively and decrease the difference of fluid flow between two strands.