Flow Simulation And Structure Optimization Of Blast Furnace Gas Waste Heat Boiler

Waste heat recovery device of blast furnace gas waste heat boiler is recovery and utilization ofironmaking process of the main by-product blast furnace gas.Simply speaking,blast furnace gas wasteheat boiler is a heat exchanger,but its internal structure and the flow and heat transfer process is verycomplicated.accurate knowledge of the flow field and temperature field inside the situation has animportant significance for optimization design waste heat boiler.Pressure at the entrance of the researchobject of flue gas of blast furnace gas waste heat boiler for300Kpa. But the generally waste heat boilerentrance flue gas is under pressure. Therefore, establishing the physical model, should pay attention tothe effect of gas pressure to bring the waste heat boiler wall.In this article，the strueture optimization andnumerical simulation of flow and temperature fields in the blast furnace gas waste heat boiler alloverinternal was researched by CFD teehnology.Based on the simulation results of flow and temperaturefields analysis,find out the internal structure defects of waste heat boiler, and research it,proposed tooptimize the structure model, Again the simulation optimization structure and gives the conclusion.In thisarticle, the main research contents and conclusions are as follows:According to the structural characteristics of blast furnace gas waste heat boiler,a boiler integratedphysical model, meshing, boundary conditions,and numerical simulation of the whole boiler model. Theboiler internal flow and temperature fields distribution law in general, the flow and temperature fieldsanalysis of simulation results, and as a basis for establishing the2optimization: structure optimizationbaffle at the hopper;according to the problem of low efficiency of particles in the ash separation,proposed in the ash hopper corner baffle to join increase the separation efficiency of particles; in thestructure optimization of flow structure around the cornerinto the draft tube: the boiler through flowstructure around the corner,the flue gas velocity temperature fields distribution is flow uneven,affect theeffect of heat transfer, join the flow tube uniformly around the corner at the corner of the velocity fieldand the heat transfer enhancement.(1) The ash hopper structure optimization: Using the two-phase model of a hopper-type HRSG andparticulate matter in the flow separation simulation, analysis hopper adding different angle stop on theflow conditions and particle separation efficiency, and according to the perspective of different diametersbaffle particle separation efficiency affect the simulation results for the hopper to optimize the structure. The results showed that: join hopper baffle particle separation is better than the original ash bucket,different angles of each baffle diameter particle separation results are greatly affected.(2) The structure optimization of flow structure:CFD technology is used to simulate the flow field inthe flow structure of a waste heat boiler. As structure of flow uneven phenomenon, put forward the ideato add through-flow conduits.Analyzes the impact of adding different number of through-flow conduits toflow field,nonuniformity coefficient and the turbulence intensity of flow structure. The structure isoptimized according to the number of through-flow conduits to Coefficient of uniformity and turbulenceintensity effects of flow simulation results. The reseach shows that: join through-flow conduits flowstructure Coefficient of uniformity and turbulence intensity were significantly better than the originalstructure. Greatly influence of the number of through-flow conduits to Coefficient of uniformity and theturbulence intensity. Accede to through-flow conduits can evenly around the corner flow and improve theeffectiveness of the heating surface of the heat transfer.The optimization of the above two optimization results is added to the waste heat boiler, structureoptimization of the heat flow and heat transfer with in the boiler. Analysis and comparison of thesimulation results to optimize the structure and original boiler model.