活性炭吸附甲醛的格子Boltzmann模拟

基于孔隙尺度，结合活性炭与甲醛的真实物性参数，利用格子Boltzmann方法，选取热质耦合的LBGK模型对填充有球形活性炭的方腔内部双扩散混合对流、流固共轭传热及吸附特性进行数值模拟。分别采用二维D2Q9模型描述速度温度场，D2Q5模型描述浓度场，研究活性炭颗粒直径、孔隙率以及颗粒的排列方式对整个动态吸附性能的影响。结果表明：在孔隙率为0.85时，随着颗粒直径的增大，活性炭吸附甲醛的速率减小，达到饱和吸附状态所需的时间增长；当直径为0.43 mm时活性炭的吸附速率最大，达到饱和状态的时间最短；活性炭颗粒的吸附速率与达到吸附饱和所需的时间几乎与孔隙率无关；与活性炭颗粒的错列与顺列排列方式相比，随机且不粘连排列方式的动态吸附性能更好。

Lattice Boltzmann Simulation of Formaldehyde Adsorption by Activated Carbon

We adopted LBGK model of heat-mass coupling in lattice Boltzmann method to simulate double diffusion mixed convection, fluid-solid conjugate heat transfer and adsorption process in an enclosure filled with spherical activated carbon with real physical parameters at pore scale. D2Q9 model was used to describe velocity and temperature fields, and D2Q5 for concentration fields, respectively. Impact of activated carbon particle size, porosity and particle arrangement on entire dynamic adsorption performance was investigated. It shows that with increased activated carbon particle size the time to approach steady is increased and the adsorption rate is moderated at porosity 0.85. At particle diameter 0.43 mm, the adsorption rate is the highest and the adsorption time is the shortest. Transient adsorption capability and time consumption to equilibrium were independent of filling rate. Compared with those of line and dislocation arrangement of activated carbon particles, transient adsorption capability of random and non-adherent arrangement is better.