Development of an Electrostatic Precipitator to Remove Martian Atmospheric Dust From ISRU Gas Intakes During Planetary Exploration Missions

作者：Clements J Sidney^*; Thompson Samuel M; Cox Nathanael D; Johansen Michael R; Williams Blakeley S; Hogue Michael D; Lowder M Loraine; Calle Carlos I

来源：IEEE Transactions on Industry Applications, 2013, 49(6): 2388-2396.

DOI：10.1109/TIA.2013.2263782

• Carbon dioxide
• corona discharge
• electrostatic precipitation (ESP)
• Martian dust
• particle charging

Manned exploration missions to Mars will need dependable in situ resource utilization (ISRU) for oxygen production. The Martian atmosphere is composed of 95.3% CO2, other gases, and 0.13% O-2 at similar to 9 mbar (1% of the Earth%26apos;s pressure). However, it also contains 2-10-mu m dust uploaded by dust devils and high winds. Oxygen extraction requires removal of the dust with little pressure drop (Delta p). An electrostatic precipitator (ESP) has lower Delta p than a filter, but the low pressure causes an electrical breakdown at electric fields (similar to 1 kV/cm) similar to 30x lower than on Earth, making implementation challenging. Molecular mean free paths (lambda = 4 mu m) and ion mobility values (b = 0.008m(2)/V . s) are similar to 100x larger than at Earth%26apos;s pressure (lambda = 44 nm) and (b = 8.4 x 10(-5)). The large lambda lowers Stokes drag, particularly for smaller particles. Pauthenier field charging dominates for particles with d %26gt; 5 mu m and diffusion charging for d %26lt; 2 mu m. The low E proportionally decreases both Pauthenier particle charging and the F = qE collection force. This greatly reduces the particle migration velocities (w), e. g., for d = 10 mu m, w = 0.01 m/s compared with 0.4 m/s on Earth. However, for small particles (d = 1 mu m), this is compensated by diffusion charging and reduced drag (w = 0.04 m/s on Mars, 0.05 m/s on Earth). The Martian atmosphere was simulated with 95% CO2/5% humid air at 9 mbar. Paschen curves were measured, and I-V curves (I similar to 5-300 mu A for V similar to 1.3-2.3 kV) were obtained for 5-10-cm-diameter wire/rod-cylinder ESPs. Only positive polarity yielded stable uniform corona. Charging of 0.5-1.3-cm-diameter spheres agreed with the Pauthenier theory. A Martian dust simulant collection efficiency test is in progress.

• 出版日期2013-12