航天器外表面导电面积对朗缪尔探针科学探测的影响

Influence of Spacecraft Conductive Surface Area on Langmuir Probe Measurement

朗缪尔探针的科学探测会受到航天器外表面导电面积与朗缪尔探针传感器有效面积之比大小的影响。如果航天器的外表面导电面积不足够大,朗缪尔探针以扫描电压模式工作时,就会造成航天器地电位的扰动,进而导致朗缪尔探针测量结果的偏差。分析了此问题的物理原理,并进行了相应的理论计算。子午工程探空火箭有效载荷朗缪尔探针在进行科学探测的同时,测量了火箭外表面导电面积与朗缪尔探针传感器有效面积之比不足造成的扰动,测量结果与理论分析基本一致。

The investigation of the Langmuir probe is limited by the ratio of the spacecraft conductive surface area to the probe effective area. If the spacecraft conductive surface area is not large enough, the spacecraft ground potential will be disturbed when Langmuir probe works in sweeping voltage mode, furthmore, the Langmuir probe results will deviate from the correct one. The physical principle of this effect is analyzed, and the corresponding calculation is given. The Langmuir probe onboard the sounding rocket of Meridian Project investigates the influence of the small area ratio of the rocket conductive sur- face to the probe, besides the scientific objects of the payload. The flight data of the Langmuir probe show the disturbances as a result of the small conductive area ratio, approximately as the prolepsis of the theory.