等离子体诊断的Ka波段透射测量系统研制与应用

在理论分析的基础上,研制了基于非接触测量条件下等离子体参数诊断的Ka波段透射测量系统.利用已知介电参数的泡沫介质棒验证了Ka波段透射测量系统的可靠性与测量精度,测试结果表明:在静态测量条件下该系统的测量误差小于1.5％.Ka波段透射测量系统应用于激波管等离子体参数诊断,获得了电子密度和碰撞频率的瞬态变化曲线.在相同实验条件下,Ka波段透射测量系统的等离子体电子密度诊断结果与朗谬尔静电双探针的测量结果较为吻合,表明该系统应用于动态等离子体诊断的结果可信,满足非接触测量条件下瞬态等离子体诊断要求.应用误差理论分析了Ka波段透射测量系统的测量误差,结果表明其相对误差小于10％.

Development and Application of Ka Band Transmission Measurement System for Plasma Diagnosis

The Ka band transmission measurement system has been developed for the diagnose plasma under noncontact measurement conditions.The measurement reliability and measurement accuracy of the system is verified by the bubble dielectric rods.The measurement errors of the dielectric constant on bubble materials measured by the system are less than 1.5％ under the conditions of the static measurement.The system has been applied to diagnose the plasma generated by shock tube.The transient characteristic curves of the plasma electron density and collision frequency are obtained by the system.The measured results obtained by the system have been compared with the ones obtained by the electrostatic probe under the same experimental conditions.The results show that diagnosis results of two methods have small difference.The diagnosis has been proved to be credible under the conditions of dynamic measurement.The system is able to meet the demands for the transient plasma diagnosis under the noncontact measurement conditions.According to theory of errors,the relative measurement error of the system is less than 10％.