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Scott Hall

Publications and source records attributed to Scott Hall.

Power Optimization of Cryogenic CO2 Deposition Capture in Deep Space

An extremely reliable cabin air revitalization system is needed for human deep space exploration missions. Deep space offers an environmental temperature close to 4 Kelvin. This low environmental temperature enables heat rejection for systems that are thermally power-intensive, i.e. CO2 cold surface deposition (CDep). The CDep system relies on phase change temperatures of air components to deposit CO2 onto a cold surface. The cold surface can be generated utilizing cryocoolers, including Stirling and Reverse Brayton, or deep space environmental temperature. This paper presents a numerical study on a power optimization of cold surface generation via a cryocooler or thermal radiator. An example system for each type is presented. However, a hybrid system would not only reduce power required to remove CO2, but also increase redundancy and reliability of the air revitalization system.

Pranav Jagtap

Low Speed Azimuthal Wave Characteristics In a Cathode Plume

A diagnostic technique to measure the azimuthally traveling m=1 mode in the plume of a cathode inside a HET-like magnetic field was developed. The data show the wave accelerating with the increasing magnetic field strength. While the azimuthal wave grows, the presence of a high frequency (>1MHz) instability appears. While the appearance of this wave and general characteristics were observed using this diagnostic technique, further full-thruster environment testing is needed to show the effects the HET beam has on these instabilities

space propulsion