船用烟气脱硫塔喷淋系统数值模拟研究

Numerical Simulation Study of Spray System of Marine Flue Gas Desulfurization Tower

喷淋系统是船用烟气脱硫塔主要功能构件,喷淋系统参数喷淋锥角、喷淋流速和喷淋流量对船用烟气脱硫塔烟气流场均匀程度影响大,影响过程复杂。以某型号船用烟气脱硫塔为基础模型,采用Design Expert软件中BBD实验方法设计了基于喷淋系统参数喷淋锥角、喷淋流速和喷淋流量的三因素三水平共17组试验,以多个截面烟气速度标准偏差平均值为评判依据对塔内烟气流动均匀性进行评判。采用ANSYS自带软件SCDM建立了船用烟气脱硫塔三维实体模型,采用Fluent meshing进行了模型网格划分,采用计算流体动力学商业软件Fluent对试验进行模拟计算。应用Design Expert软件对17组试验结果进行二次回归分析,应用Matlab遗传算法工具箱对二次回归分析得到的目标函数关系式求解,得到各截面流速标准偏差平均值最小时喷淋流速、喷淋锥角、喷淋流量的对应值,再次应用Fluent软件对优化结果进行了验证,可靠度达97.40%。

The spray system is the main functional component of marine flue gas desulphurization tower,and the spray system parameters spray cone angle,spray flow velocity,and spray flow rate have a great influence on the uniformity of the flue gas flow field of marine flue gas desulphurization tower,and the influence process is complicated.Taking a certain type of marine flue gas desulphurization tower as the basic model,the BBD experimental method in Design Expert software was used to design a total of 17 groups of tests based on the three factors and three levels of the spray system parameters of spray cone angle,spray flow velocity and spray flow rate,and the average of the standard deviation of flue gas velocity of a number of cross-sections was used as the basis for judging the uniformity of the flue gas flow in the tower.The three-dimensional solid model of the marine flue gas desulphurization tower was established by using ANSYS software SCDM,the model meshing was carried out by using Fluent meshing,and the experiments were simulated by using Fluent,a commercial software for Computational Fluid Dynamics(CFD).Design Expert software was applied to carry out quadratic regression analysis on 17 groups of experimental results,and Matlab Genetic Algorithm Toolbox was applied to solve the objective function equation obtained from the quadratic regression analysis to obtain the corresponding values of spray flow velocity,spray cone angle and spray flow rate at the smallest time of the average value of standard deviation of flow rate of each cross-section,and the optimization results were verified by Fluent software again,and the reliability reached 97.40%.