Numerical simulation study on the enhancement of cyclone separator in CFB boilers
Cyclone separator separation performance can significantly affect circulating fluidized bed boiler operation.In order to solve the problem of poor separator performance of cyclone separator in a 300 MW circulating fluidized bed boil-er,based on the Euler-Lagrange framework,firstly,a full loop geometric model of the furnace,cyclone separator and re-turn valve of the 300 MW circulating fluidized bed boiler was established by ug software according to the actual size of 1:1,and then the boundary conditions were set according to the actual parameters,and then numerical simulation was carried out by Barracuda software.Numerical simulations were carried out by Barracuda software to analyze the effects of the flue inlet parameters of the cyclone separator:inlet flue height,inlet flue width,inlet downward tilt angle and the in-sertion depth of the center cylinder on the cyclone separator efficiency and pressure drop.The deviation between the simulated and actual values of the pressure in the furnace chamber is within 5%,and the simulation results are relatively accurate.Considering the separation efficiency,pressure drop and wear and tear of the separator,two modification schemes are proposed.Simulation results show that the two schemes can improve the cyclone separator separation per-formance at all loads,the efficiency of Scheme Ⅰ at full load is improved by 0.26%and the pressure drop is reduced by 13.1 Pa compared with that before the retrofit,and the efficiency of Scheme Ⅱ at full load is improved by 0.24%and the pressure drop is reduced by 53.7 Pa compared with that before the retrofit;with the reduction of the load,the efficiency improvement is not obvious gradually,and the efficiency improvement is not obvious at 300 MW,260 MW and 160 MW loads,Scheme Ⅰ improves the efficiency of the separator by 0.26%,0.178%,and 0.023%,respectively,and Scheme Ⅱ improves it by 0.24%,0.174%,and 0.02%,respectively.