Experimental Study Of The EAST Tokamak Density Fluctuation Reflectometer

In the diagnosis of high-temperature plasma,In order to comprehensively understand the behavior of the plasma,we always want to put some so-called "probe" substances into the plasma,by studying the interaction of these probes with plasma to detect the relevant parameters of the plasma.The "probe" used by the microwave reflector is a wide range of electromagnetic waves,and its effect on the high temperature plasma is very weak,that is,a non-perturbed diagnosis of the plasma.By measuring the electromagnetic wave in the plasma cutoff layer,the density and fluctuation of the plasma are measured.This paper discusses the system construction and related physical research work of multi-channel poloidal correlation reflectometry on EAST.For the hardware part,the design parameters of the system and the test results of the system hardware are introduced,including the polarization Of the system,the selection of microwave source,the arrangement of the antenna array and the data collection system.At the same time,the test results of the key components of the system are introduced,Combined with the actual situation,given the rationality of the analysis.In the physical research,we discuss some preliminary experimental results in Auxiliary heating of low hybrid wave: we can accurately recognize the time the L-H transition by spectrum analysis of the reflector signal,and in the ELM-free phase after entering the H-mode,the coherent mode with frequency of 40-50 KHz and then gradually increased to 100 KHz was observed.The density of the coherent mode was obtained by density inversion.Moreover,through the correlation analysis of the signal,the poloidal wave number of the density fluctuation is obtained,and the rotation direction is the ion drift direction.In the second part,the basic principle of microwave reflectometer diagnosis is introduced.The third chapter mainly introduces EAST multi-channel correlation reflectometer system.The fourth chapter mainly focuses on the laboratory test and the initial experimental results on EAST in Auxiliary heating of low hybrid wave.Finally,the author summarizes the main work of the master’s degree and prospects the future research work.