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Understanding the effects of dynamic thermal and vacuum regeneration on VOC desorption kinetics is needed for the development of regenerable trace contaminant control air revitalization systems. The effects of temperature and vacuum quality on the desorption kinetics of ethanol from Carbosieve SIII were examined using 1 hour regeneration cycles. The effect of vacuum quality on ethanol desorption was studied by exposing adsorption tubes loaded with ethanol to low pressures (1.0, 0.5, 0.3, and 0.12 atm) at various thermal regeneration temperatures (160, 100, 70, and 25 °C). At 1 atm of pressure, ethanol removal was found to increase from 2% at 25 °C, to 25% at 70 °C, to 55% at 100 °C, and to 77% at 160 °C. Decreasing the atmospheric pressure from 1 to 0.1 atm for 1 hr did not significantly enhance Carbosieve SIII regeneration at ambient temperatures (25 °C). However, heating the adsorbent at low pressures enhanced its regeneration.

The Technology Test Bed and Hydrogen Cold Flow facilities at NASA’s Marshall Space Flight Center (MSFC) in Huntsville, Alabama provide unique testing capabilities for the aerospace community. Located at the Advanced Engine Test Facility (AETF), these facilities are operated and maintained by MSFC Propulsion Laboratory personnel. They provide a systems and components level testing platform for validating new technology concepts and advanced systems design and for gaining a better understanding of test article internal environments. A discussion follows of the particular capabilities of each facility to provide a range of testing options for specific test articles.

For an optimum design, the weight, energy consumption, and operational flexibility of the traction drive system for a lunar roving vehicle must be considered along with the power supply, motor, and power train. Other problems considered in this paper include: environment and motor dissipation; motor type (a-c or d-c) and commutation if d-c; motor controller (switching of large currents); delivery of torque at varying speeds; the power train; use of regenerative braking and conservation of energy; and power supply voltage variation. These problems are studied in the light of certain general system specifications, which fall into weight, performance, and environment categories. Tradeoff studies are considered for purposes of optimization in each of these areas. Special consideration is given to the controller and system design as it pertains to regenerative braking and the conservation of energy.