纺丝法制备聚合物中空纤维膜过程中的流动及其稳定性研究

Since the continuing development of the membrane science and technology, polymer hollow fiber membranes have been applied to many fields. At present, most polymer hollow fiber membranes in the industry are performed by spinning process based on the transition principle of immersion precipitation. The spinning process involves many problems of fluid mechanics. Especially the interfacial instability of the polymer solution is the key problem to study. This program will study the spinning process of polymer hollow fiber membranes from the view of fluid mechanics. Using the computational fluid dynamics (CFD) method to numerically simulate the convection during the spinning process, solve the steady axisymmetric or three dimensional unsteady governing equations of fluid mechanics, to give the distribution of velocity, temperature and concentration fields. Study the interfacial instability by linear stability analysis, to give the condition and pattern of the interfacial instability. Thereby to predict the size and surface structure of the polymer hollow fiber membranes performed on various condition, and to give the best condition to prepare the polymer hollow fiber membranes with various property, and to provide the scientific foundation to prepare the ideal polymer hollow fiber membranes.

随着膜科学与技术的不断发展,聚合物中空纤维膜在众多领域得到了广泛的应用。目前工业界绝大部分的聚合物中空纤维膜采用基于浸没沉淀相变原理的纺丝法制备。纺丝法的制备过程中涉及大量的流体力学问题，特别是聚合物溶液界面的稳定性问题需要重点研究。本项目拟从流体力学角度对纺丝法制备聚合物中空纤维膜过程开展研究。运用计算流体力学方法，数值模拟制备过程中的流动问题,求解定常轴对称或三维非定常地流体力学控制方程组，给出流场、温度场和浓度场的分布。采用线性稳定性分析方法研究溶液界面的稳定性，给出界面失稳的条件和失稳模式。从而预测各参数条件下制备的聚合物中空纤维膜的尺寸和表面形貌，给出不同性能聚合物中空纤维膜的最优制备条件，为制备理想的聚合物中空纤维膜提供科学依据。

随着膜科学与技术的不断发展,聚合物中空纤维膜在众多领域得到了广泛的应用。目前工业界绝大部分的聚合物中空纤维膜采用基于浸没沉淀相变原理的纺丝法制备。纺丝法的制备过程中涉及大量的流体力学问题，特别是聚合物溶液界面的稳定性问题需要重点研究。本项目拟从流体力学角度对纺丝法制备聚合物中空纤维膜过程开展研究。运用计算流体力学方法，数值模拟制备过程中的流动问题,求解定常轴对称或三维非定常地流体力学控制方程组，给出流场、温度场和浓度场的分布。采用线性稳定性分析方法研究溶液界面的稳定性，给出界面失稳的条件和失稳模式。从而预测各参数条件下制备的聚合物中空纤维膜的尺寸和表面形貌，给出不同性能聚合物中空纤维膜的最优制备条件，为制备理想的聚合物中空纤维膜提供科学依据。