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This paper describes a program to develop a miniaturized chemical laboratory (μChemLab™). This system includes multiple analysis channels each with microfabricated sample collectors/concentrators, gas chromatographic separators, and chemically selective detectors based on an array of coated surface acoustic wave devices. This development effort is currently focused on fabricating small (palm-top computer sized), lightweight, and autonomous systems that provide rapid (1 min), sensitive (1-10 ppb), and selective detection of chemical warfare agents. The small size and low power of the μChemLab™ technology make it potentially useful for monitoring of compounds such as volatile organic compounds (VOCs), ammonia, and formaldehyde in space environments.

The absolute measurement of low-density gases, especially water, is of interest to space experiments. Water measurements have been advanced by the development of a primary standard for low-density water vapor. This standard, which uses arrays of laser-drilled holes as a Knudsen-effusion water source, was used to calibrate and characterize the performance of several vacuum instruments, including transfer standards used to calibrate the MSX flight mass spectrometer. This mass spectrometer and a total pressure sensor will be used to measure the absolute densities of molecules outgassing from the spacecraft during orbit as well as gases present in the ambient atmosphere. Results for the performance of these two flight instruments over a large range of partial pressures of H2O, H2, He, N2, O2 and Ar are presented, as well as test results for the reference standards.

As a part of NASA’s efforts in space, options are being examined for an Artemis moon base project to be deployed. This project requires a system of interconnected, but separate, DC microgrids for habitation, mining, and fuel processing. This in-place use of power resources is called in-situ resource utilization (ISRU). These microgrids are to be separated by 9-12 km and each contains a photovoltaic (PV) source, energy storage systems (ESS), and a variety of loads, separated by level of criticality in operation. The separate microgrids need to be able to transfer power between themselves in cases where there are generation shortfall, faults, or other failures in order to keep more critical loads running and ensure safety of personnel and the success of mission goals. In this work, a 2 grid microgrid system is analyzed involving a habitation unit and a mining unit separated by a tie line.

An approximation method for evaluation of the caloric equations used in combustion chemistry simulations is described. The method is applied to generate the equations of specific heat, static enthalpy, and Gibb's free energy for fuel mixtures of interest to gas turbine engine manufacturers. Liquid-phase fuel properties are also derived. The fuels include JP-8, synthetic fuel, and two fuel blends consisting of a mixture of JP-8 and synthetic fuel. The complete set of fuel property equations for both phases are implemented into a computational fluid dynamics (CFD) flow solver database, and multi-phase, reacting flow simulations of a well-tested liquid-fueled combustor are performed. The simulations are a first step in understanding combustion system performance and operational issues when using alternate fuels, at practical engine operating conditions.