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由于同时具备机械捕获和静电吸附两种除尘机制,驻极体滤料具有更高的过滤效率,在微细颗粒物净化中得到越来越广泛的应用.本文利用格子波尔兹曼耦合离散单元法模拟研究了顺排、叉排、随机排列三种纤维排布方式下清洁和含尘驻极体滤料过滤性能的差异.模拟过程中详细考虑了颗粒和纤维间的粘附碰撞过程.研究结果表明,较普通滤料,驻极体滤料对大尺度中性颗粒捕获能力的促进作用更强;随着颗粒在纤维表面的沉积,驻极体滤料和普通滤料对中性颗粒捕集效率的差异逐步趋小.对于布朗扩散为主的细颗粒,均匀排布(顺排和叉排)时滤料捕集效率较随机排布时更大;而对于惯性和拦截效应为主的较大尺度颗粒,叉排排布时滤料捕集效率较顺排和随机排列大.“,”The electret filter could obtain high filtration efficiency with low resistance to the air flow due to its additional electrostatic attraction mechanism,thus it has been widely used for separating airborne particle from air stream.In the present study,the lattice Boltzmann coupled with discrete element method is employed to investigate the filtration performance of clean and dust-loaded electret filters.The adhesive contact processes between the fiber and the particle are well considered in the model.Three fiber arrangement modes,namely parallel model,staggered model and random arrangement model are compared.Results show that the electret filter plays stronger role in enhancing filtration performance with the increase in particle diameter.With the deposition of particles,the capture efficiency differences between normal filter and electret filter is narrowed.The electret filters with parallel and staggered arrangements have larger capture efficiency than that with random arrangement when diffusional capture mechanism is dominant.While,in inertial and interception dominant regimes,the electret filter with staggered arrangement obtains the largest capture efficiency among the three fiber arrangement modes.