本文以Nylon 6/FA溶液研究電紡絲過程中泰勒錐內流場，並探討Nylon 6濃度對流場的影響。通過在Nylon 6/FA溶液中加入少量玻璃珠並以綠光雷射照射泰勒錐即可觀察玻璃珠的流動以了解泰勒錐內的流場，這種技術被稱為粒子影像測速。藉由分析玻璃珠的速度可得知泰勒錐內溶液的流速數量級為1 mm/s，且拉伸速率遠小於Nylon 6/FA溶液的鬆弛速率，表明在泰勒錐內不會發生流動誘導相分離。

以高速攝影機觀察電紡Nylon 6/FA溶液時的液柱行為，可發現筆直液柱有左右擺動的現象，此現象應該與液柱內部發生流動誘導相分離有關。探討濃度對液柱左右擺動頻率的影響，發現Nylon 6濃度增加液柱左右擺動頻率下降。

This study investigated the electrospinning process of Nylon 6/FA solutions, focusing on the flow field inside the Taylor cone and the impact of Nylon 6 concentration on this flow. It also aimed to determine the relationship between the flow field inside Taylor cone and the morphology of the as-spun fibers collected on the grounded collector. By adding small amounts of glass spheres to the electrospinning solutions and using a green laser to illuminate the Taylor cone, particle image velocimetry was employed to observe the movement of the glass spheres. It was found that for lower concentrations (7 wt.% and 11 wt.%), there was a recirculation flow inside the Taylor cone, while higher concentrations (15 wt.% and 21 wt.%) showed direct downward flow into the fluid jet. The flow velocity inside the Taylor cone was determined to be around 1 mm/s, and the extension rate induced by electric field was found to be much lower than the relaxation rate of the Nylon 6/FA solution, indicating that flow-induced phase separation did not occur inside the Taylor cone.

Additionally, high-speed camera observations of the electrospinning jet revealed lateral vibrations in the straight jet region, which were likely related to flow-induced phase separation within the jet. The study found that as the concentration of Nylon 6 increased, the frequency of these oscillations decreased.

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