纤维直径分布及均匀性是影响纤维制品在实际使用过程中的关键因素。近年来静电纺丝产业化日趋成熟，但纤维直径离散度大产品质量不可控，制备窄分布的静电纺微纳米纤维十分紧迫。本研究将充分考虑自由液面上多射流抽拔不稳定的特点，建立窄分布空间对称喷头自由液面临界条件下纺丝的准静态模型，分析空间对称电场分布及多射流的均匀性分布问题，研究微纳米纤维直径窄分布的内在机理，构建空间对称喷头下窄分布微纳米纤维形成的四阶段射流/电场两相流模型，充分考虑射流产生的随机性以及相互间的干扰不稳定性。利用Ansoft Maxwell电磁模拟软件对喷头在高压静电场作用下的电场强度进行仿真模拟，对制备的微纳米纤维的直径及其分布进行分析，并做大量实验工作来验证理论的准确性。结果应用于普遍的无针头静电纺丝技术，预测和控制批量制备微纳米纤维的质量，进一步提高和优化微纳米纤维的品质。为高质量微纳米纤维的国产化提供理论基础和技术支持。

The distribution and uniformity of fiber diameter are the key factors that affect the actual use of fiber products. In recent years, the industrialization of electrospinning is becoming more and more mature. However, the fiber diameter dispersion is wide, and the quality of products is not controllable. It is very urgent to prepare narrow-distributed electrospun micro/nanofiber. This study will fully consider the characteristics of free surface jet pulling instability. A quasi-static model of narrow-distributed-diameter-fiber spinning on free surface of the symmetric nozzle at critical condition will be established to analyze the electric field distribution and uniformity of multi jets. Then, understand the internal mechanism of micro/nano fiber diameter and narrow distribution while establishing the model of four stage jets and electric field two-phase flow. The.randomness of the jets and the instability of the interference are taken into full consideration. Using Ansoft Maxwell electromagnetic simulation software to simulate the electric field intensity of the nozzle under the action of high voltage electrostatic field and analyze the theory accuracy of diameter distribution of the prepared micro/nanofibers after a large number of experiments. The results will be applied to general needle free electrospinning technology for predicting and controlling the quality of batch preparation of micro/nanofiber, which will further optimize the quality of the fibers. It provides theoretical basis and technical support for the localization of high quality micro/nanofiber.