Study On Flow Behaviour And Optimization In Spray Bed Of Quench Chamber

The flow field inside the quench ring and the vertical falling film flow inside dip tube were mainly researched in the thesis. A three-dimensional numerical simulation was performed to study the interior flow field and flow rate distribution at outlet of experimental and industrial-scale quench ring. The distribution of the liquid film and the influence factors in dip tube of new-type quench chamber were investigated. In addition, the experimental and numerical simulation study of the structure optimization of quench ring was carried out.The predicted mass flow rate distribution of jet holes of experimental-scale quench ring was in good agreement with the experimental data, which validates the feasibility of three-dimensional numerical models applied in this thesis. The simulation results of industrial-scale quench ring with four90mm-diameter water inlets indicated that the value of flow rate percentage of jet holes was lower than the area percentage. The flow rate has the minimum at the circumferential direction where the water inlet lies.The distribution of the liquid film and the effect of flow rate of inlets, slot width of quench ring and the gas velocity in the dip tube were investigated by two parallel-wire conductance probes. The results showed that the liquid film distributed inhomogeneously at the entrance region. It was also found that film thickness increased with increasing flow rate at water inlet. The comparison of the characteristics of the liquid film flow inside of dip tube with different inlet structures were discussed in detail, and based on the uniformity and the fluctuation of falling film and the interior flow field inside of quench ring, the structure of the inlet of quench ring was optimized. The quench ring with inclined slab in inlet has good performance on the uniformity and the fluctuation of falling flow film inside of dip tube.