驻极体纳米纤维非稳态过滤性能的介观尺度研究

项目名称： 驻极体纳米纤维非稳态过滤性能的介观尺度研究

项目编号： No.51506058

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 能源与动力工程

项目作者： 蔡容容

作者单位： 华南理工大学

项目金额： 21万元

中文摘要： 驻极体纳米纤维过滤高效、低阻、节能，是一种新型室内颗粒物净化技术。驻极体纳米纤维储有电荷、直径小，由于静电场和微尺度效应的影响，其过滤性能、过滤机制与普通纤维相比存在显著差异，目前对它们的认识还很不足，大大限制了该技术在工程上的应用。本项目拟从造成过滤性能动态变化的本源-颗粒沉积现象出发，研究颗粒在不同驻极体纳米纤维上的沉积行为特征，及其对过滤效率和压降的动态影响规律；从介观尺度揭示驻极体纳米纤维的非稳态过滤机制，明晰纤维性质对过滤性能的影响规律，为驻极体纳米纤维净化技术奠定理论基础。主要包括：基于非稳态过滤测试结果，建立纳米纤维的非稳态过滤性能模型，用于直观描述过滤性能随时间的动态变化规律；从纳米纤维和颗粒间的微观相互作用本质出发，建立考虑能量耗散效应的微细颗粒物粘附碰撞动力学参数模型；LB-DEM模拟多场耦合下颗粒沉积过程，分析总结沉积行为对纳米纤维过滤性能、机制的影响规律。

中文关键词： 可吸入颗粒物；驻极体纳米纤维；LB-DEM数值模拟；非稳态；颗粒沉积

英文摘要： Electret nanofiber filter is a promising indoor particulate matter purification technology due to its properties of high efficiency, low pressure drop and energy-saving. Electret nanofiber storages charge, and has small fiber diameter and high dust capacity. Due to the electrostatic effect and micro-scale effect, its dynamic filtration performance and mechanism are quite different from that of the common fibers. Current understanding of them are still inadequate, which greatly limits its application in engineering. The research intends to study the particle deposition behavior on the electret nanofibers, and its impact on the filtration efficiency and pressure drop. The aim is to reveal the transient filtration mechanism of the electret nanofiber from the mesoscopic scale, and lay a theoretical foundation for the application of the electret nanofiber purification technology. The research contents include following sections. Based on the experimental results of the transient filtration, the phenomenological model of transient filtration performance of the electret nanofiber will be established, which can be used to visually describe the dynamic changes of the filtration efficiency and pressure drop with the time. Based on the comprehensive analysis on the microscopic interaction between the nanofibers and the particles, and the energy dissipation mechanisms, a complete dynamic parameter model for particle impact process will be developed. After that, the deposition process of the particle on the electret nanofiber will be simulated using LB-DEM. On the basis of experimental and simulation results, the influence of the deposition behavior on the nanofiber filtration performance and filtration mechanism will be analyzed and summarized.

英文关键词： inhalable particle;electret nanofiber;LB-DEM simulation;transient;particle deposit