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Coming Soon - Development of Free Molecule Flow Equations from a Transient, Asymmetric Source

Molecular flow model is explored as a tool to describe an unusual variety of plume interaction issues. Goddard Space Flight Center, Greenbelt, Maryland The analysis and simulation of gases expanding from sources such as rocket nozzles into vacuum, or the effects plumes from these sources create when they interact with solid surfaces, present a considerable challenge to the scientific and engineering communities. As a plume expands into vacuum, density levels, and hence collision rates, decrease rapidly by many orders of magnitude. The main difficulty lies in accurately describing a flow field extending from continuum flow at the nozzle exit, through the transition regime, and reaching free molecule behavior within a relatively short distance downstream. For thrusters, flow at the nozzle exit is usually characterized by high exit velocities and relatively high Mach numbers. Even in regions where significant intermolecular collision rates occur, relative velocity levels are low, and little thermal scattering occurs normal to the mainly radial streamlines. Such observations lead one to consider describing the expansion under certain circumstances using free molecule theory.

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Bird Vision System

This system is applicable to commercial airports and military airfields where the likelihood of bird strikes is high, and for environmental studies. John F. Kennedy Space Center, Florida About 2.5 seconds after the launch of STS-114, the first Return to Flight launch after the Columbia accident, a large bird struck the external tank and fell into the exhaust plume. While this particular bird strike did not threaten the vehicle because it did not strike the orbiter, it did raise awareness of the threat of avian fauna present at launch. In response to the avian threat, a Bird Radar system was developed to detect birds above the launch pad. Because of interference with launch systems, the radar system could not span closer than a few hundred feet above the pad. There was a gap region that would not be visible with the radar.

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Selective Access and Editing in a Database

Ames Research Center, Moffett Field, California A complex organization with many tasks and sub-tasks, many phases, and many workers often will have an associated database with many users and groups, each of whom has a limited “need to know” (e.g. fine-grained security access controls) that does not extend to all information in the database. A group of users having access to information in a particular portion of the database may need to edit one or more documents to restate the original information more conveniently or accurately.

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Integrated Science Instrument Module (ISIM) Reconfigurable Packet Tool

Goddard Space Flight Center, Greenbelt, Maryland This tool supports the development of table loads required to inform the flight software of new on-the-fly packet definitions. The main outcome of the processing includes all the database products needed by the ground system to process the newly created packets. The tool ingests the latest telemetry definition from the James Webb Space Telescope (JWST) central database repository, and updates those definitions as required to support the dynamic packet definitions determined by the user of the tool. These updated telemetry definitions are in a form that can be directly sent to the JWST central database repository for inclusion in a new database version. The tool allows for the inclusion in the new packet definitions of any ISIM Flight Software (FSW) data types.

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Program Determines When MRO Observations Span More Than One Spacecraft Sequencing Period

NASA’s Jet Propulsion Laboratory, Pasadena, California Previously, the Mars Reconnaissance Orbiter (MRO) did not allow observations to go beyond the end of a planning period. However, opportunities for observing the Mars Science Laboratory (MSL) rover occur close enough to these boundaries to require the observations that support the rover to cross these boundaries. This requires the observation to be included in two planning cycles.

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Build, Assemble, Test (BAT) Planning and Execution Resources Application

NASA’s Jet Propulsion Laboratory, Pasadena, California BAT is a Web-based application used for the assembly and inspection of critical flight and associated ground support hardware for JPL missions that are developed in-house. It is used to capture and communicate data that is unique to a part or assembly that cannot be captured in an engineering drawing or a test procedure. It includes a list of parts and tools, along with specific steps required for building and assembling a piece of hardware.

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Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA)

John H. Glenn Research Center, Cleveland, Ohio The current steady-state performance-based system studies are not adequate to evaluate certain advanced technologies for the challenges associated with meeting the transient performance requirements without better definition and control of component operating margins. Additional dynamic analyses would require more detailed, physics-based, component-level models and controllers in order to better identify dynamic issues that may arise during operation of the engine. The additional complexity in these models increases the effort necessary throughout the design processes, including the system-analysis step. The solution would be a physics-based engine model with full envelope controller. C-MAPSS and C-MAPSS40k are examples of engine models with full envelope controllers, but because they are designed to model a specific engine, they are not good candidates for systems analysis.

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