长江科学院院报2025，Vol.42Issue(6)：71-77,7.DOI:10.11988/ckyyb.20240389
不同离子强度下饱和多孔介质中多分散颗粒沉积特征
Deposition Characteristics of Polydisperse Particles in Saturated Porous Media under Different Ionic Strengths
摘要
Abstract
[Objectives]Polydisperse particles are widely present in natural environments.Accurately predicting the transport and deposition of polydisperse particles in saturated media under unfavorable conditions(where repul-sive forces exist between particle and medium surfaces)is crucial.[Methods]A series of constant-flow one-di-mensional sand column experiments with artificial recharge were conducted using polydisperse particles(0.375-18.863 μm)under different ionic strength conditions(1,6,20,and 200 mM).Deposition characteristics of polydisperse particles under different ionic strengths(unfavorable and favorable conditions)were investigated.By coupling the colloid attachment efficiency model under unfavorable conditions with the polydisperse particle deposi-tion model,a deposition model for polydisperse particles under unfavorable conditions was established,and corre-sponding numerical simulations were performed.[Results]Both physical experiments and numerical simulations showed that under favorable conditions,the capture probability of polydisperse particles exhibited a non-monotonic V-shaped characteristic of first decreasing and then increasing with particle size due to uneven micro-force distribu-tion.Compared with favorable conditions,the repulsive double-layer force between polydisperse particles and the medium surface under unfavorable conditions formed an energy barrier,leading to an 8.5％-67.6％ reduction in capture probability.The smaller the particle size,the greater the reduction in particle capture probability.Under fa-vorable conditions,the final deposition profile curve of particles exhibited a hyper-exponential distribution with"upper-steep,lower-gentle".The total deposition amount increased with increasing ionic strength,with 16.7％-24.6％ of the total deposition occurring in the upper part of the sand column.A decrease in ionic strength exacerba-ted the uneven"upper-steep,lower-gentle"distribution of the deposition profile.[Conclusions]The research re-sults not only further reveal the transport and deposition characteristics of polydisperse particles under natural unfa-vorable conditions,but also provide a scientific basis for effective watershed water quality management.关键词
多分散颗粒/沉积特征/离子强度/数值模拟/能量势垒/吸附效率/超指数分布Key words
polydisperse particles/deposition characteristics/ionic strength/numerical simulation/energy barrier/attachment efficiency/hyper-exponential distribution分类
建筑与水利引用本文复制引用
邹志科,余蕾,李亚龙,牛书瑶,乔伟,边久..不同离子强度下饱和多孔介质中多分散颗粒沉积特征[J].长江科学院院报,2025,42(6):71-77,7.基金项目
国家自然科学基金青年项目(42202276) （42202276）
武汉市知识创新专项曙光计划项目(2022020801020243,CKSD2022363/NY) （2022020801020243,CKSD2022363/NY）
安徽省自然科学基金项目水科学联合基金项目(2208085US10) （2208085US10）
