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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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At least 127 records · Page 7

The Dynamics of Miscible Fluids: A Space Flight Experiment (MIDAS)

We propose a space flight experiment to study the dynamics of miscible interfaces. A less viscous fluid displaces one of higher viscosity within a tube. The two fluids are miscible in all proportions. An intruding "finger" forms that occupies a fraction of the tube. As time progresses diffusion at the interface combined with flow induced straining between the two fluids modifies the concentration and velocity distributions within the whole tube. Also, under such circumstances it has been proposed that the interfacial stresses could depend on the local concentration gradients (Korteweg stresses) and that the divergence of the velocity need not be zero, even though the flow is incompressible. We have obtained reasonable agreement for the tip velocity between numerical simulations (that ignored the Korteweg stress and divergence effects) and physical experiments only at high Peclet Numbers. However at moderate to low Pe agreement was poor. As one possibility we attributed this lack of agreement to the disregard of these effects. We propose a space experiment to measure the finger shape, tip velocity, and the velocity and concentration fields. From intercomparisons between the experiment and the calculations we can then extract values for the coefficients of the Korteweg stress terms and confirm or deny the importance of these stresses.

Maxworthy, T.↗

The Dynamics of Miscible Fluids: A Space Flight Experiment (MIDAS)

We propose a space flight experiment to study the dynamics of miscible interfaces. A less viscous fluid displaces one of higher viscosity within a tube. The two fluids are miscible in all proportions. An intruding "finger" forms that occupies a fraction of the tube. As time progresses diffusion at the interface combined with flow induced straining between the two fluids modifies the concentration and velocity distributions within the whole tube. Also, under such circumstances it has been proposed that the interfacial stresses could depend on the local concentration gradients (Korteweg stresses) and that the divergence of the velocity need not be zero, even though the flow is incompressible. We have obtained reasonable agreement for the tip velocity between numerical simulations (that ignored the Korteweg stress and divergence effects) and physical experiments only at high Peelet Numbers. However at moderate to low Pe agreement was poor. As one possibility we attributed this lack of agreement to the disregard of these effects. We propose a space experiment to measure the finger shape, tip velocity, and the velocity and concentration fields. From intercomparisons between the experiment and the calculations we can then extract values for the coefficients of the Korteweg stress terms and confirm or deny the importance of these stresses.

Maxworthy, T.↗

Flight Technical Error Analysis of the SATS Higher Volume Operations Simulation and Flight Experiments

This paper provides an analysis of Flight Technical Error (FTE) from recent SATS experiments, called the Higher Volume Operations (HVO) Simulation and Flight experiments, which NASA conducted to determine pilot acceptability of the HVO concept for normal operating conditions. Reported are FTE results from simulation and flight experiment data indicating the SATS HVO concept is viable and acceptable to low-time instrument rated pilots when compared with today s system (baseline). Described is the comparative FTE analysis of lateral, vertical, and airspeed deviations from the baseline and SATS HVO experimental flight procedures. Based on FTE analysis, all evaluation subjects, low-time instrument-rated pilots, flew the HVO procedures safely and proficiently in comparison to today s system. In all cases, the results of the flight experiment validated the results of the simulation experiment and confirm the utility of the simulation platform for comparative Human in the Loop (HITL) studies of SATS HVO and Baseline operations.

Williams, Daniel M.↗

Manned Space Flight Experiments Symposium: Gemini Missions III and IV

This is a compilation of papers on in-flight experiments presented at the first symposium of a series, Manned Space Flight Experiments Symposium, sponsored by the National Aeronautics and Space Administration. The results of experiments conducted during the Gemini Missions III and IV are covered. These symposiums are to be conducted for the scientific community at regular intervals on the results of experiments carried out in conjunction with manned space flights.

RADIATION ABSORPTION↗

Design and Implementation of the Boundary Layer Transition Flight Experiment on Space Shuttle Discovery

In an effort to better the understanding of high speed aerodynamics, a series of flight experiments were installed on Space Shuttle Discovery during the STS-119 and STS-128 missions. This experiment, known as the Boundary Layer Transition Flight Experiment (BLTFE), provided the technical community with actual entry flight data from a known height protuberance at Mach numbers at and above Mach 15. Any such data above Mach 15 is irreproducible in a laboratory setting. Years of effort have been invested in obtaining this valuable data, and many obstacles had to be overcome in order to ensure the success of implementing an Orbiter modification. Many Space Shuttle systems were involved in the installation of appropriate components that revealed 'concurrent engineering' was a key integration tool. This allowed the coordination of all various parts and pieces which had to be sequenced appropriately and installed at the right time. Several issues encountered include Orbiter configuration and access, design requirements versus current layout, implementing the modification versus typical processing timelines, and optimizing the engineering design cycles and changes. Open lines of communication within the entire modification team were essential to project success as the team was spread out across the United States, from NASA Kennedy Space Center in Florida, to NASA Johnson Space Center in Texas, to Boeing Huntington Beach, California among others. The forum permits the discussion of processing concerns from the design phase to the implementation phase, which eventually saw the successful flights and data acquisition on STS-119 in March 2009 and on STS-128 in September 2009.

Spanos, Theodoros A.↗

A note on an acoustic response during an engine nacelle flight experiment

During a flight test study of the noise effects on laminar flow on the outside surface of a simulated engine nacelle, an intense acoustic response was observed. The aircraft speed at which this signal occurred and the frequency content of the signal fell within the test conditions of the experiment and had to be eliminated prior to continuing. The signal was identified as an aerodynamic excitation of an acoustic mode in the simulated by-pass duct of the nacelle. By modifying the trailing edges of the support struts of the nacelle, the aerodynamic excitation was changed enough to eliminate the resonant response of the offending duct modes, eliminating the unwanted acoustic problem.

Schoenster, James A.↗

Adaptive Structures Flight Experiments

The topics are presented in viewgraph form and include the following: adaptive structures flight experiments; enhanced resolution using active vibration suppression; Advanced Controls Technology Experiment (ACTEX); ACTEX program status; ACTEX-2; ACTEX-2 program status; modular control patch; STRV-1b Cryocooler Vibration Suppression Experiment; STRV-1b program status; Precision Optical Bench Experiment (PROBE); Clementine Spacecraft Configuration; TECHSAT all-composite spacecraft; Inexpensive Structures and Materials Flight Experiment (INFLEX); and INFLEX program status.

Martin, Maurice↗

Infrared Imaging of Boundary Layer Transition Flight Experiments

The Hypersonic Thermodynamic Infrared Measurement (HYTHIRM) project is presently focused on near term support to the Shuttle program through the development of an infrared imaging capability of sufficient spatial and temporal resolution to augment existing on-board Orbiter instrumentation. Significant progress has been made with the identification and inventory of relevant existing optical imaging assets and the development, maturation, and validation of simulation and modeling tools for assessment and mission planning purposes, which were intended to lead to the best strategies and assets for successful acquisition of quantitative global surface temperature data on the Shuttle during entry. However, there are longer-term goals of providing global infrared imaging support to other flight projects as well. A status of HYTHIRM from the perspective of how two NASA-sponsored boundary layer transition flight experiments could benefit by infrared measurements is provided. Those two flight projects are the Hypersonic Boundary layer Transition (HyBoLT) flight experiment and the Shuttle Boundary Layer Transition Flight Experiment (BLT FE), which are both intended for reducing uncertainties associated with the extrapolation of wind tunnel derived transition correlations for flight application. Thus, the criticality of obtaining high quality flight data along with the impact it would provide to the Shuttle program damage assessment process are discussed. Two recent wind tunnel efforts that were intended as risk mitigation in terms of quantifying the transition process and resulting turbulent wedge locations are briefly reviewed. Progress is being made towards finalizing an imaging strategy in support of the Shuttle BLT FE, however there are no plans currently to image HyBoLT.

Berry, Scott A.↗

Optimization of moisture content for wheat seedling germination in a cellulose acetate medium for a space flight experiment

The Porous Tube Plant Nutrient Delivery System (PTPNDS), a hydrophilic, microporous ceramic tube hydroponic system designed for microgravity, will be tested in a middeck locker of the Space Shuttle. The flight experiment will focus on hardware operation and assess its ability to support seed germination and early seedling growth in microgravity. The water controlling system of the PTPNDS hardware has been successfully tested during the parabolic flight of the KC-135. One challenge to the development of the space flight experiment was to devise a method of holding seeds to the cylindrical porous tube. The seed-holder must provide water and air to the seed, absorb water from the porous tube, withstand sterilization, provide a clear path for shoots and roots to emerge, and be composed of flight qualified materials. In preparation for the flight experiment, a wheat seed-holder has been designed that utilizes a cellulose acetate plug to facilitate imbibition and to hold the wheat seeds in contact with the porous tube in the correct orientation during the vibration of launch and the microgravity environment of orbit. Germination and growth studies with wheat at a range of temperatures showed that optimal moisture was 78% (by weight) in the cellulose acetate seed holders. These and other design considerations are discussed.

NASA Discipline Number 61-20↗

Space flight experience with the Shuttle Orbiter control system

Experience gained through the Shuttle Orbital Flight Test program has matured the engineering understanding of the Shuttle on-orbit control system. The geneology of the control systems (called digital autopilots, or DAPs, and used by the Shuttle for on-orbit operations) is reviewed, the flight experience gained during the flight test program is examined within the context of preflight analysis and test results, and issues for the operational phase of the Shuttle, including constraints upon both operations and analysis still required to increase confidence in the Shuttle's ability to handle capabilities not experienced during the flight test program are addressed. Two orbital autopilots have resulted from computer memory and time constraints on a flight control system, with many different, flight phase unique requirements. The transition DAP, used for insertion and deorbit, has more active sensors and redundancy but a less complex data processing scheme excluding state estimation with fewer choices of operational mode.

Cox, K. J.↗

Aeroassist Flight Experiment Reaction Control System preliminary design

The Aeroassist Flight Experiment (AFE) has several different flight modes associated with its mission. The effect the spacecraft attitude control system (ACS) has on the Reaction Control System (RCS) requirements for all the flight modes is discussed. The ACS requirements and their consequences on the design of the RCS is then discussed in detail. Special problems in the RCS design unique to the AFE mission and the design solutions to these problems are presented.

Langford, G. K.↗

Boundary Layer Transition Flight Experiment Overview and In-Situ Measurements

In support of the Boundary Layer Transition Flight Experiment (BLTFE) Project, a manufactured protuberance tile was installed on the port wing of Space Shuttle Orbiter Discovery for the flights of STS-119 and STS-128. Additional instrumentation was also installed in order to obtain more spatially resolved measurements downstream of the protuberance. This paper provides an overview of the BLTFE Project, including the project history, organizations involved, and motivations for the flight experiment. Significant efforts were made to place the protuberance at an appropriate location on the Orbiter and to design the protuberance to withstand the expected environments. Efforts were also extended to understand the as-fabricated shape of the protuberance and the thermal protection system tile configuration surrounding the protuberance. A high-level overview of the in-situ flight data is presented, along with a summary of the comparisons between pre- and post-flight analysis predictions and flight data. Comparisons show that predictions for boundary layer transition onset time closely match the flight data, while predicted temperatures were significantly higher than observed flight temperatures.

Anderson, Brian P.↗

BLT Flight Experiment Overview and In-Situ Measurements

In support of the Boundary Layer Transition Flight Experiment (BLT FE) Project, a manufactured protuberance tile was installed on the port wing of Space Shuttle Orbiter Discovery for the flight of STS-119. Additional instrumentation was also installed in order to obtain more spatially resolved measurements. This paper will provide an overview of the BLT FE Project, including the project history, organizations involved, and motivations for the flight experiment. Significant efforts were made to place the protuberance at an appropriate location on the Orbiter and to design the protuberance to withstand the expected environments. Efforts were also extended to understand the as-fabricated shape of the protuberance and the thermal protection system tile configuration surrounding the protuberance. A high level overview of the in-situ flight data will be presented, along with a summary of the comparisons between pre- and post-flight analysis predictions and flight data.

Anderson, Brian P.↗

The superfluid helium on-orbit transfer (SHOOT) flight experiment

The SHOOT flight demonstration is being undertaken to verify component and system level technology necessary to resupply large superfluid helium dewars in space. The baseline configuration uses two identical 210 liter dewars connected by a transfer line which contains a quick disconnect coupling. The helium will be transferred back and forth between the dewars under various conditions of flow rate, parasitic heat load, and temperature. An astronaut Extra-vehicular Activity (EVA) is also planned to manually demate and mate the coupling. A number of components necessary for the flight are being developed. These components are described here.

Dipirro, Michael J.↗

Tile Surface Thermocouple Measurement Challenges from the Orbiter Boundary Layer Transition Flight Experiment

Hypersonic entry flight testing motivated by efforts seeking to characterize boundary layer transition on the Space Shuttle Orbiters have identified challenges in our ability to acquire high quality quantitative surface temperature measurements versus time. Five missions near the end of the Space Shuttle Program implemented a tile surface protuberance as a boundary layer trip together with tile surface thermocouples to capture temperature measurements during entry. Similar engineering implementations of these measurements on Discovery and Endeavor demonstrated unexpected measurement voltage response during the high heating portion of the entry trajectory. An assessment has been performed to characterize possible causes of the issues experienced during STS-119, STS-128, STS-131, STS-133 and STS-134 as well as similar issues encountered during other orbiter entries.

Charles H. Campbell↗

Flight Experience and Lessons Learned From Biosentinel: A 6u Deep Space Cubesat

This paper reviews the flight experiences of the BioSentinel propulsion and At-titude Determination and Control System (ADCS) teams. BioSentinel, a 6U CubeSat, launched as a secondary aboard the Space Launch System (SLS) maid-en flight in November of 2022 and is now operating in an Earth trailing helio-centric orbit. The development and performance of a novel approach to gyro bias estimation in the spacecraft’s Sun safe controller is discussed in detail. Further-more, the development and in-flight experience with the spacecraft’s propulsion system is discussed. Finally, we present the development and execution of an angular momentum management approach developed in flight after a propulsion system valve failure.

BioSentinel↗

Flight Experience and Lessons Learned from BioSentinel: A 6U Deep Space CubeSat

This presentation reviews the flight experiences of the BioSentinel propulsion and At-titude Determination and Control System (ADCS) teams. BioSentinel, a 6U CubeSat, launched as a secondary aboard the Space Launch System (SLS) maid-en flight in November of 2022 and is now operating in an Earth trailing helio-centric orbit. The development and performance of a novel approach to gyro bias estimation in the spacecraft’s Sun safe controller is discussed in detail. Further-more, the development and in-flight experience with the spacecraft’s propulsion system is discussed. Finally, we present the development and execution of an angular momentum management approach developed in flight after a propulsion system valve failure.

Jesse Fusco↗

Vertical Lunar Regolith Conveying as a Flight Experiment in Simulated Lunar-Gravity

Regolith conveying will be an essential task for supplying regolith feedstock to In-Situ Resource Utilization (ISRU) reactor systems for regolith processing on the Moon and Mars. The Vertical Lunar Regolith Conveyor (VLRC) is a technology being developed at NASA Kennedy Space Center (KSC) as a regolith transport task for the GCD ISRU FLEET project led by NASA Glenn Research Center (GRC). Single test loop versions of the VLRC are being developed at NASA KSC as a technology demonstration for a flight experiment. The NASA Flight Opportunities program selected the VLRC for a technology demonstration opportunity on a future Blue Origin New Shepard suborbital launch vehicle to study regolith transport physics in a relevant environment in a vacuum chamber under simulated lunar gravity conditions in order to advance its technology readiness level (TRL) for future space applications. The VLRC system includes four primary subsystems to achieve the objectives of the lunar gravity (Lunar-G) flight experiment. (1) An eccentric vibratory conveyor stack to convey regolith particles consisting of three single-loop helical surface conveyors with each actuated by two vibratory motors that vibrate in unison. One of the three single-loops contains a 0.8°-3.1° inclined helical path and the other two contain a 1.6°-6.2° incline. (2) A stick-slip conveyor stack to convey regolith particles consisting of three single-loop helical surface conveyors with each actuated by the same motor to move in unison in a stick-slip motion. One of the three single-loops contains a 0.8°-3.1° inclined helical path and the other two contain a 1.6°-6.2° incline. (3) A regolith containment system to contain the regolith in each single-loop track during launch before the start of the experiment using containment caps that will be lifted in unison at the start of Lunar-G. (4) COTS cameras will record the motion of regolith and tracer particles. Post-flight analysis of the videos will be used to determine convey speeds and flow rates. The VLRC experiment will use the well-known technique of Particle Image Velocimetry (PIV) image analysis to determine the velocity of tracer particles entrained in the regolith flow. This velocity will be used to calculate the mass flow rate of the regolith being conveyed.

ISRU↗