Micro-Tube Plasmas (μTP) have been gaining attention for applications ranging from medicine to material science and analytical chemistry due to their small size, low cost of operation and flexibility. In the present work a specific μTP, known as the Flexible Micro Tube Plasma (FμTP) is investigated experimentally and, for the first time, numerically as well. The creation, propagation mechanisms and properties of the ionization waves inside the microtube are investigated during the positive and negative half cycle of a μs square wave applied voltage. A two-dimensional (2D) axi-symmetric numerical model is developed and compared with optical emission spectroscopy showing good agreement. During the positive half cycle the plasma propagates as an ionization wave (or streamer) depositing charges on the dielectric wall. During the negative half cycle the plasma propagates due to the neutralization of those surface charges on the walls. The different propagation mechanisms affect the accumulation of charges, the induced electric field, and the speed of the ionization waves.

微管等离子体 (μTP) 因其体积小、操作成本低和灵活性高而在从医学到材料科学和分析化学的应用中受到关注。在目前的工作中，一种称为柔性微管等离子体 (FμTP) 的特定 μTP 进行了实验研究，并且第一次也进行了数值研究。在 μs 方波施加电压的正负半周期间，研究了微管内电离波的产生、传播机制和特性。开发了二维 (2D) 轴对称数值模型，并与显示良好一致性的光学发射光谱进行了比较。在正半周期间，等离子体以电离波（或流光）的形式传播，在电介质壁上沉积电荷。在负半周期间，由于壁上的那些表面电荷的中和，等离子体传播。不同的传播机制会影响电荷的积累、感应电场和电离波的速度。