Aljahdaly Noufe H, El-Tantawy S A
Department of Mathematics, Faculty of Sciences and Arts-Rabigh Campus, King Abdulaziz University, Rabigh, 21911 Jeddah, Saudi Arabia.
Centre for Physics Research (CPR), Department of Physics, Faculty of Science and Arts, Al-Baha University, Al-Baha, 1988 Al-Mikhwah, Saudi Arabia.
Chaos. 2020 May;30(5):053117. doi: 10.1063/1.5132557.
In this work, the dynamic mechanism scenario of nonlinear electrostatic structures (unmodulated and modulated waves) that can propagate in multi-ion plasmas with the mixture of sulfur hexafluoride and argon gas is reported. For this purpose, the fluid equations of the multi-ion plasma species are reduced to the evolution (nonplanar Gardner) equation using the reductive perturbation technique. Until now, it has been known that the solution of nonplanar Gardner equation is not possible and for stimulating our data, it will solve numerically. At that point, the present study is divided into two parts: the first one is analyzing planar and nonplanar Gardner equations using the Adomian decomposition method (ADM) for investigating the unmodulated structures such as solitary waves. Moreover, a comparison between the analytical and numerical simulation solutions for the planar Gardner equation is examined, showing how powerful the ADM is in finding solutions in the short domain as well as its fast convergence, i.e., the approximate solution is consistent with the analytical solution for the planar Gardner equation after a few iterations. Second, the modulated envelope structures such as freak waves (FWs) are investigated in the framework of the Gardner equation by transforming this equation to the nonlinear Schrödinger equation (NLSE). Again, the ADM is used to solve the NLSE for studying FWs numerically. Furthermore, the effect of physical parameters of the plasma environment (e.g., Ar-SF -F-SF plasma) on the characteristics of the nonlinear pulse profile is elaborated. These results help in a better understanding of the fundamental mechanisms of fluid physics governing the plasma processes.
在这项工作中，报道了可在含有六氟化硫和氩气混合物的多离子等离子体中传播的非线性静电结构（未调制和调制波）的动力学机制情形。为此，使用约化摄动技术将多离子等离子体物种的流体方程简化为演化（非平面加德纳）方程。到目前为止，已知非平面加德纳方程的解是不可能的，为了处理我们的数据，将对其进行数值求解。此时，本研究分为两部分：第一部分是使用阿多米安分解法（ADM）分析平面和非平面加德纳方程，以研究诸如孤立波之类的未调制结构。此外，还检验了平面加德纳方程解析解与数值模拟解之间的比较，展示了ADM在短域内求解的强大能力及其快速收敛性，即经过几次迭代后，近似解与平面加德纳方程的解析解一致。第二，通过将加德纳方程转换为非线性薛定谔方程（NLSE），在加德纳方程的框架内研究诸如怪波（FWs）之类的调制包络结构。同样，使用ADM求解NLSE以对FWs进行数值研究。此外，阐述了等离子体环境（例如，Ar - SF - F - SF等离子体）的物理参数对非线性脉冲轮廓特征的影响。这些结果有助于更好地理解控制等离子体过程的流体物理基本机制。
