离心中间包内钢液流动的数值模拟

NUMERICAL SIMULATION OF MOLTEN STEEL FLOW IN CENTRIFUGAL FLOW TUNDISH

采用数值模拟方法对离心中间包内钢液的流动结构及混合特性进行了研究,并用水模型结果进行了验证.流场的研究结果表明:旋转室内强烈的湍流极大地促进了夹杂物的湍流碰撞生长.另外,在旋转室切向出流的影响下,分配室内形成了较大的水平环流.环流的形成增强了钢液的混合程度,且延长了夹杂物沿着液面运动的距离,增大了夹杂物的去除机会.对钢液停留时间分布(RTD)的预测结果表明:由于钢液的旋转流动,离心中间包内的死区体积明显减小,活塞区及混流区体积增加,从而夹杂物的上浮去除率提高.

Flow structure and mixing characteristic in centrifugal flow tundish were investigated by mathematical simulation method, and the simulation results were verified with the measurement data obtained from water model. Flow field results show that strong turbulence in the rotation chamber greatly promotes the growth rate of inclusion owing to the turbulence coagulation. Besides, a large scale horizontal circumfluence is formed in the distribution chamber under the effect of tangential outflow. The formation of circumfluence promotes the mixing of molten steel and prolongs the distance that inclusions move close to the slag, thereby increases the possibility for the removal of inclusions. Prediction result of the residence time distribution （RTD） shows that as a result of the swirling flow in the rotation chamber, the dead volume in the tundish is reduced, plug volume and mix volume are increased so that the inclusion removal effieiency is improved.