多模式离子推力器流率特性实验研究

为了实现多模式离子推力器在宽功率范围内最优性能和可靠性,基于30cm多模式离子推力器通过实验开展了阴极和中和器羽状模式转变点流率、放电电压30V对应阴极流率和放电损耗曲线与束电流关系研究。30cm多模式离子推力器束电流从0.3A增加到3.3A时,阴极羽状模式转变点流率值从0.017mg/s增加到0.163mg/s,放电电压30V对应阴极流率从0.129mg/s增加到0.231mg/s,中和器羽状模式转变点流率从0.030mg/s增加到0.191mg/s。随放电室工质利用率的增加,在小束电流下放电损耗迅速增加；当束电流大于1.5A时,放电损耗对放电室工质利用率的变化较为迟钝。基于上述流率特性实验结果完成了30cm多模式离子推力器宽功率范围35个工作点下最佳流率设计。在设计的工作流率下,放电电压小于30V,阴极和中和器均工作在点状模式,实测推力为9.6mN~185.2mN、比冲为1332s~3568s、功率为258W~4761W。

Experimental Study on Flow Rate Characteristic of Multi-Mode Ion Thruster

To maximize the performance and reliability of the ion thruster at all operating modes over a wide range of power, the cathode and neutralizer plume mode transition flow rate, the cathode flow rate corresponding to discharge voltage 30V and discharge loss curve versus on beam current have been investigated by a diameter of 30cm multi-modes ion thruster. When the 30cm multi-modes ion thruster beam current increased from 0.3A to 3.3A, the cathode plume mode transition flow rate increased from 0.017mg/s to 0.163mg/s, the cathode flow rate corresponding to discharge voltage 30V increased from 0.129mg/s to 0.231mg/s, and the neutralizer cathode plume mode transition flow rate increased from 0.030mg/s to 0.191mg/s. With the increase of discharge propellant utilization efficiency, discharge loss increased sharply as beam current less than 1.5A. By contrast, discharge loss increased slowly as beam current larger than 1.5A. Basing on these results the optimal flow rates of the 30cm multi-modes ion thruster at the 35 operating modes over a power range from 0.3kW to 5kW was designed and evaluated. The experimental results showed that the discharge voltage of 30cm multi-modes ion thruster less than 30V, and the cathode and neutralizer operated under spot mode, as well as the measured thrust was 9.6mN~185.2mN and specific impulse was 1332s~3568s at the power of 258W~4761W.