The Flow Field Characteristics Of Pouring Molten Iron Process And The Migration Of Associated Pollutants

There are a lot of industrial production existing the process of pouring, in which the high temperature liquid material is poured from the feeding tank to the receiving tank. During the liquid materials falling, the air around the receiving tank is induced and entrained into it. According to the law of conservation of mass, the gas will escape from the opening of the receiving tank. As a consequence the gas develops into the buoyant jet with high temperature and initial velocity, which not only contains some waste heat and masses of harmful gas, also contains lots of dust particles. These will seriously affect the air quality of the workshop and cause great harm to the health of workers.Therefore, the process of pouring the molten iron from the ladle furnace to the converter has important research value.In this paper, the CFD method is adopted to the research of the molten iron pouring process, based on two phase flow model of the FLUENT commercial software, and the dynamic mesh technique is applied. At last, the numerical simulation about the process of pouring molten iron from the ladle furnace is accomplished.First, a simple two-dimensional model is established to discuss and verify the characteristics of the buoyant jet and plume. In the article, a new method is come up with, that two-phase flow model is applied to the simulation of the plume flow, which contains the molten iron area and the surround gas area, and the simulation results are almost consistent with the single-phase flow.Second, the whole molten water pouring process is divided into three stages, that is,“Pre-pouring”, ”Pouring” and “After-pouring”, according to the phase interface changes.The dividing line between stage 1 and stage 2 is whether the molten iron runs out from the iron water tank and enters the converter. It is stage 3 that the molten water is all poured into the converter. The flow field is more stable, and the velocity is small, the gas movement belongs to buoyant plume flow in the first stage. The second stage, the complex flow field, the velocity fluctuations, mainly relies on the interaction of the buoyant plume and buoyant jet. In the third stage, the velocity gradually stabilized, and it’s a transition from buoyant jet to plume.Last, the migration of gas, caused by buoyancy and momentum, is over the ladle furnace and the converter, along with the surrounding gas and dust. Combined with practical engineering problems about the hood installing, a truncation surface is selected above the ladle furnace and the converter, then focus on the average velocity of the truncation surface during the pouring process. It is more intuitive to guide industrial ventilation from the trend of the average velocity of truncation surface.