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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Heater placed between an oil diffusion pump and a vacuum chamber prevents backstreaming of oil molecules into the work area of the chamber. It breaks the oil molecules into basic constituents that can be pumped away.
As fusion and other applications that require tritium processing capabilities become more prominent worldwide, it begins to strain the supply of tritium compatible pumps. In order to help alleviate the supply chain bottleneck, alternatives need to be identified that can help reduce the required number of tritium compatible pumps to strictly the primary process loop where tritium concentrations are high. This research is aimed at identifying vacuum pumps that can be used in low tritium environments (e.g., glovebox stripper systems, adsorbent regeneration, flush gas/inert line evacuation, etc.)
The ultimate utility of hydrogen masers as highly accurate clocks aboard navigation satellites depends on the feasibility of making the maser lightweight, compact, and capable of a 5 to 7 year unattended operation. A vacuum pumping system for the maser that is believed to meet these criteria was designed and fabricated. The pumping system was fabricated almost completely from 6Al-4V titanium alloy and incorporates two or four sintered zirconium carbon getter pumps with integral activation heaters. The manner in which the getter pumps were mounted to insure that they will stand both the activation and the shock of launch is illustrated. Data on the total hydrogen capacity and pumping of this system is also presented.
Moist soil introduced in vacuum chamber to determine pumping load and time required
The success of NASA's future space missions and the development of portable, commercial instrument packages will depend greatly on miniaturized components enabled by the use of microelectromechanical systems (MEMS).
This poster briefly highlights the challenge the senior design team was tasked with, and the events that led up to the ultimate solution. Described within the poster are problem statements, the design tasks that were formed based on the problem statement, the design processes and deliverables of the project, as well as the project outcome/impact.
A filter system for mechanical pumps is designed with a baffle assembly that rotates in a circulating oil bath which traps destructive particles. This prevents severe damage to the pump and is serviceable for long periods before it requires cleaning.
System provides high pumping capacity even for noble gases. First stage, removes water and CO2 from input gas. Second stage, removes noble gases except helium and some lighter gases not trapped by first stage. Third stage, traps all remaining gases. All three stages mounted inside liquid-nitrogen Dewar that cools first stage. Pump small enough for general laboratory use.
Large diffuser operations envelope and long run times possible. Jet engine driven ejector/diffuser system combines two turbojet engines and variable-area-ratio ejector in two stages. Applications in such industrial proesses as handling corrosive fumes, evaporation of milk and fruit juices, petroleum distillation, and dehydration of blood plasma and penicillin.
Creare Incorporated and NASA Goddard Space Flight Center developed and space qualified two wide range pumps (WRPs) that were included in the Sample Analysis at Mars (SAM) instrument. This instrument was subsequently integrated into the Mars Science Laboratory (MSL) "Curiosity Rover," launched aboard an Atlas V rocket in 2011, and landed on August 6, 2012, in the Gale Crater on Mars. The pumps have now operated for more than 18 months in the Gale Crater and have been evacuating the key components of the SAM instrument: a quadrupole mass spectrometer, a tunable laser spectrometer, and six gas chromatograph columns. In this paper, we describe the main design challenges and the ways in which they were solved. This includes the custom design of a miniaturized, high-speed motor to drive the turbo drag pump rotor, analysis of rotor dynamics for super critical operation, and bearing/lubricant design/selection.
NIU 2026 Senior Design Showcase
Pressure-gage calibration, mass-spectrometer leak detector measures leakage rates up to 300 times greater than its normal limit. Approach utilizes constant-volume displacement characteristic of mechanical vacuum pump. Vacuum system must be small for calibration measurement validity and reduction of outgassing.
Chamber provides cold, vacuum, low-background-radiation environment and optical and electrical feedthroughs needed for testing and calibration of planar arrays of long-wavelength infrared photodetectors. Equipped with multiple ports for vacuum pumps, vacuum gauges, cryogenic fluids, sources of radiation, and camera heads. Accommodates variety of infrared sources, detectors, and associated equipment for testing at temperatures down to about 4.2 K in low-background-radiation environment.
Diffusion and ion pump vacuum systems using ionic and kinetic methods of gas evacuation
High vacuum centrifugal molecular distillation system rapidly reclaims contaminated diffusion pump oil in continuous operation and restores it to high level of purity.
Differential ion pumping for vacuum deposition of thin films
Miniature scroll pumps have been proposed as roughing pumps (low - vacuum pumps) for miniature scientific instruments (e.g., portable mass spectrometers and gas analyzers) that depend on vacuum. The larger scroll pumps used as roughing pumps in some older vacuum systems are fabricated by conventional machining. Typically, such an older scroll pump includes (1) an electric motor with an eccentric shaft to generate orbital motion of a scroll and (2) conventional bearings to restrict the orbital motion to a circle. The proposed miniature scroll pumps would differ from the prior, larger ones in both design and fabrication. A miniature scroll pump would include two scrolls: one mounted on a stationary baseplate and one on a flexure stage (see figure). An electromagnetic actuator in the form of two pairs of voice coils in a push-pull configuration would make the flexure stage move in the desired circular orbit. The capacitance between the scrolls would be monitored to provide position (gap) feedback to a control system that would adjust the drive signals applied to the voice coils to maintain the circular orbit as needed for precise sealing of the scrolls. To minimize power consumption and maximize precision of control, the flexure stage would be driven at the frequency of its mechanical resonance. The miniaturization of these pumps would entail both operational and manufacturing tolerances of <1 m. Such tight tolerances cannot be achieved easily by conventional machining of high-aspect-ratio structures like those of scroll-pump components. In addition, the vibrations of conventional motors and ball bearings exceed these tight tolerances by an order of magnitude. Therefore, the proposed pumps would be fabricated by the microfabrication method known by the German acronym LIGA ( lithographie, galvanoformung, abformung, which means lithography, electroforming, molding) because LIGA has been shown to be capable of providing the required tolerances at large aspect ratios.
Testing high power electric propulsion devices poses unique requirements on space simulation facilities. Very high pumping speeds are required to maintain high vacuum levels while handling large volumes of exhaust products. These pumping speeds are significantly higher than those available in most existing vacuum facilities. There is also a requirement for relatively large vacuum chamber dimensions to minimize facility wall/thruster plume interactions and to accommodate far field plume diagnostic measurements. A 4.57 m (15 ft) diameter by 19.2 m (63 ft) long vacuum chamber at NASA Lewis Research Center is described. The chamber utilizes oil diffusion pumps in combination with cryopanels to achieve high vacuum pumping speeds at high vacuum levels. The facility is computer controlled for all phases of operation from start-up, through testing, to shutdown. The computer control system increases the utilization of the facility and reduces the manpower requirements needed for facility operations.