碘工质电推进系统的储供设计及实验研究

Feeding Design and Experimental Study of Iodine Electric Propulsion System

关键词:  碘工质电推进系统  储供系统  复合加热  微流量控制  高密度贮存

Key words:  Iodine electric propulsion system  Feeding system  Combined heating  Microflow control  High density storage

摘要:

碘工质以其低成本、低压且高密度贮存等特点越来越受到重视，承担固气相变和流量供给功能的储供系统是碘工质电推进系统的关键组件。为了提高直接影响阴极和推力器性能的流量供给准确性和稳定性，设计了可采用多种加热方式的碘工质储供系统，结合用于真空舱内的高精度质量传感器，实现了流量的动态监测及mg/s级别的碘蒸气流量控制。针对储罐外部加热、内部辐射加热以及二者复合加热三种加热方式开展实验测量，探究其对流量大小和稳定性的影响规律。结果表明，三种加热方式在满足实验所需条件下均可长期供给稳定流量，辐射加热式的响应时间最快，仅需要10min左右，而外部加热则超过1h；复合加热的方式热控调节虽更为复杂，但可以进一步降低功耗。

Abstract:

Iodine has been paid more and more attention because of its low cost and low pressure and high density storage. Iodine feeding system， the key component of iodine electric propulsion system， bears the function of solid-gas phase change and flow supply. In order to improve the accuracy and stability of the flow supply which directly affects the performance of the cathode and the thruster， a new iodine storage and feeding system was designed and can be heated in various ways， with a high-precision weight sensor used in vacuum chambers， which realizes the dynamic flow monitoring and the iodine vapor flow control at the mg/s level. Three thermal control methods of external heating， internal radiative heating and combined heating of the tank were tested and measured to explore the law of their influence on the flow rate and stability. The results show that the three heating methods can supply stable flow for a long time under the conditions required by the experiment. Radiative heating has the fastest response time， taking only about 10 minutes， compared with more than an hour for external heating. Combined heating is more complicated， but it can further reduce the power consumption.