磁激等离子体超声速气流的瞬态加速系统及其实验研究

研制了基于激波风洞的热电离系统,设计了马赫数Ma=1.5的喷管和分段法拉第型实验段,并选用了合理的磁场及电场方案。采用氦气驱动氩气模式,通过在激波管低压段注入电离种子K₂CO₃粉末实现气流的热电离;压缩后的高温氩气启动喷管,以瞬态超声速导电流体形式通过实验段。实验结果表明:当激波管高压段压力为1.1 MPa、低压段压力为500 Pa时,喷管出口的超声速导电气流温度约为4 185.91 K,压力约为0.037 MPa;当电容电压为400 V、磁感应强度为1.0 T时,由实验段中间位置电极的放电特性可以估算出气流电导率约为78.1 S/m,单对电极输入功率约为9.46 kW;用感应电压法对加速效果进行初步评估,出口气流速度增加了29.3%,电效率为26.1%。

Transient Acceleration System of Magnetoplasmadynamic Supersonic Airstream and Its Experimental Research

A hot ionization experimental system based on a shock tunnel is developed.A supersonic nozzle(Mach number Ma=1.5) and a test section(segmented Faraday accelerator) are scientifically designed as well as a magnetic & electric field scheme.Helium is chosen as the driver gas while argon as the driven gas,and ionization of the airstream is realized by adding K2CO3 powder into the driven section.The compressed argon with a high temperature drives the nozzle and creates a transient supersonic electric airstream in the test section.The experimental results are as follows: the temperature and pressure of the airstream is 4 185.91 K and 0.037 MPa respectively under the condition of 1.1 MPa driver pressure and 500 Pa driven pressure;when voltage of capacitor is 400 V and magnetic induction is 1.0 T,the electric conductivity is estimated to be 78.1 S/m with a 9.46 kW input power obtained by analyzing the discharge data of a single electrode pair;the speed of the outlet airstream is evaluated to register an increase of 29.3% and the electric efficiency is shown to be approximately 26.1% as calculated by the induced voltage.