Engineering topics

Sweterlitsch, Jeff

Publications and source records attributed to Sweterlitsch, Jeff.

6 records

NASA NTRS2012

Potential Uses of Deep Space Cooling for Exploration Missions

Nearly all exploration missions envisioned by NASA provide the capability to view deep space and thus to reject heat to a very low temperature environment. Environmental sink temperatures approach as low as 4 Kelvin providing a natural capability to support separation and heat rejection processes that would otherwise be power and hardware intensive in terrestrial applications. For example, radiative heat transfer can be harnessed to cryogenically remove atmospheric contaminants such as carbon dioxide (CO2). Long duration differential temperatures on sunlit versus shadowed sides of the vehicle could be used to drive thermoelectric power generation. Rejection of heat from cryogenic propellant could counter temperature increases thus avoiding the need to vent propellants. These potential uses of deep space cooling will be addressed in this paper with the benefits and practical considerations of such approaches.

Chambliss, Joe↗

NASA NTRS2012

Capability of the Gas Analysis and Testing Laboratory at the NASA Johnson Space Center

The Gas Analysis and Testing Laboratory is an integral part of the testing performed at the NASA Johnson Space Center. The Gas Analysis and Testing Laboratory is a high performance laboratory providing real time analytical instruments to support manned and unmanned testing. The lab utilizes precision gas chromatographs, gas analyzers and spectrophotometers to support the technology development programs within the NASA community. The Gas Analysis and Testing Laboratory works with a wide variety of customers and provides engineering support for user-specified applications in compressed gas, chemical analysis, general and research laboratory.

Broerman, Craig↗

NASA NTRS2011

Potential Uses of Deep Space Cooling for Exploration Missions

Nearly all exploration missions envisioned by NASA provide the capability to view deep space and thus to reject heat to a very low temperature environment. Environmental sink temperatures approach as low as 4 Kelvin providing a natural capability to support separation and heat rejection processes that would otherwise be power and hardware intensive in terrestrial applications. For example, radiative heat transfer can be harnessed to cryogenically remove atmospheric contaminants such as carbon dioxide (CO2). Long duration differential temperatures on sunlit versus shadowed sides of the vehicle could be used to drive thermoelectric power generation. Rejection of heat from cryogenic propellant could avoid temperature increase thus avoiding the need to vent propellants. These potential uses of deep space cooling will be addressed in this paper with the benefits and practical considerations of such approaches.

Chambliss, Joseph↗

NASA NTRS2011

Bench-Scale Trace Contaminant Testing of SA9T at Ambient and Reduced Pressure Conditions

A principal concern for air revitalization technology in a closed loop system is the capability to control carbon dioxide (CO2) and humidity (H2O). An amine based sorbent technology, SA9T, has been evaluated for use in this application and several programs are evaluating it for use in both cabin and space suit applications. While the CO2 and H2O performance of the sorbent has been tested extensively, the question of how trace contaminants impact performance requires further evaluation. This paper presents experimental results of bench-scale SA9T testing that was performed under a variety of test conditions and with several different trace contaminants. Tests were conducted to determine if the capacity of the SA9T media to sufficiently remove CO2 and H2O is compromised after exposure to a fully saturated trace contaminant at ambient conditions. Tests also were conducted to evaluate the performance of SA9T at ambient conditions in a continuous 30-day test with a mixed trace contaminant stream. In addition, testing also evaluated the impact of CO2 and H2O removal performance at suit loop pressures (29.6 KPa/4.3 psia) during cyclic operation with a constant inlet contaminant load.

Broerman, Craig↗

NASA NTRS2011

Capability of the Gas Analysis and Testing Laboratory at the NASA Johnson Space Center

Broerman, Craig↗

NASA NTRS2009

Design and Testing of Trace Contaminant Injection and Monitoring Systems

In support of the Carbon dioxide And Moisture Removal Amine Swing-bed (CAMRAS) testing, a contaminant injection system as well as a contaminant monitoring system has been developed by the Johnson Space Center Air Revitalization Systems (JSC-ARS) team. The contaminant injection system has been designed to provide trace level concentrations of contaminants generated by humans in a closed environment during space flight missions. The contaminant injection system continuously injects contaminants from three gas cylinders, two liquid reservoirs and three permeation ovens. The contaminant monitoring system has been designed to provide real time gas analysis with accurate flow, humidity and gas concentration measurements for collection during test. The contaminant monitoring system consists of an analytical real time gas analyzer, a carbon monoxide sensor, and an analyzer for ammonia and water vapor.

Broerman, Craig D.↗