Production of super-Alfvenic plasma flow and elucidation of magneto-plasma fluid dynamics with structural change

点击翻译按钮获取中文摘要

In this research we have carried out various experiments for the following purposes.(1) Realization of wide range of ion Mach number M_i and Alfven Mach number M_A parameters.(2) Verification of the extended Bernouilli's equation in a high-beta plasma flow,(3) Establishment of the experimental evaluation method of an adiabatic exponent in a fast-flowing plasma,(4) Elucidation of magneto-plasma dynamics in a super-Alfvenic flow associated with structural change of magnetic field.In order to establish control method of the Mach numbers and to perform various experimental researches in a super-Alfvenic plasma flow, a magneto-plasma-dynamic arcjet (MPDA) was modified and small magnetic coil was attached to form magnetic nozzle at the muzzle of the improved MPDA.A multiple-reflection type visible light laser interferometer was equipped for electron density measurement near the MPDA exit, and the electron density in the magnetic nozzle region was measured.We have also measured plasma flow dynamics in various magnetic configurations, especially utilizing the combination between ion heating and magnetic nozzle. A super-Alfvenic plasma flow was successfully generated and plasma flows were realized in a wide range of M_i, and M_A parameters.In order to analyze the plasma flow dynamics, it is necessary to evaluate the adiabatic exponent of ions experimentally. There was no research to measure the adiabatic exponent experimentally until now. We have established the evaluation method of an adiabatic exponent from the behavior of fast-flowing plasmas in magnetic nozzle. It was also able to clarify temporal evolution of the adiabatic exponent.As a result, we have established the generation and control method of fast-flowing plasma, and clarified experimentally dynamics of fast-flowing plasmas in a wide range of M_i and M_A parameters. In this research, we have obtained a lot of important knowledge related to various plasma physics and applied researches.