静电纺纳米纤维的纺程形态模拟

The Shape Simulation of Process on Electrospinning Nanofibers

采用计算流体动力学(CFD)对静电纺射流进行计算机模拟,采用POLYFLOW软件在二维空间上对稳定段射流的运动形态进行2D模拟,采用FLUENT软件对不稳定段射流运动形态进行3D模拟.采用专用前处理软件GAMBIT建立几何模型和生成网格.模拟结果显示:当溶液流速不变时,射流直径随牵伸力的增加而变小;但当牵伸力太大时,射流在运动的过程中不再仅仅是变细,在某一位置会出现先变粗再变细的情况;当牵伸力达到一定程度时,稳定射流消失.对于不稳定射流的模拟结果发现:在牵伸力小的情况下,射流容易发生弯曲;在牵伸力大的情况下,射流发生弯曲的位置即不稳定点离喷头远.模拟结果与实验结果十分吻合.

Computational fluid dynamics （CFD） was used to simulate electrospinning jets, POLYFLOW was chosen to simulate steady jet movement in 2D space, FLUENT was chosen to simulate insteady jet movement in 3D space, and GAMBIT was used to build geometric model and plot grid. The simulation results indicated that when solution volumetric flow rate was kept constant, jet diameter became thin easily with draw force increasing. But when draw force was too great, there were rough knot and suddenly thinning appeared along jet. When draw force reached a value, stable jet disappeared during electrospinning. To insteady jet, the jet was bending easily when the draw force was small and the distance was far from the insteady point when the draw force was big. The simulating results were quite agreed with the experiments.