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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 1,765 records · Page 98

All sources NASA NTRS DOE OSTI

NASA NTRS2014

Flexible Polyimide Aerogel Cross-linked by Poly(maleic Anhydride-alt-alkylene)

Aerogels are potential materials for aerospace applications due to their lower thermal conductivity, lighter weight, and low dielectric constant. However, silica aerogels are restricted due to their inherent fragility, hygroscopic nature, and poor mechanical properties, especially in extreme aerospace environments. In order to fit the needs of aerospace applications, developing new thermal insulation materials that are flexible, and moisture resistant is needed. To this end, we fabricated a series of polyimide aerogels crosslinked with different poly(maleic anhydride-alt-alkylene)s as seen in Scheme 1. The polyimide oligomers were made with 3,3,4,4-biphenyltetracarboxylic dianhydride (BPDA), and different diamines or diamine combinations. The resulting aerogels have low density (0.06 gcm3 to 0.16 gcm3) and high surface area (240-440 m2g). The effect of the different backbone structures on density, shrinkage, porosity, surface area, mechanical properties, moisture resistance and thermal properties will be discussed. These novel polyalkylene-imide aerogels may be potential candidates for applications such as space suit insulation for planetary surface missions, insulation for inflatable structures for habitats, inflatable aerodynamic decelerators for entry, descent and landing (EDL) operations, and cryotank insulation for advance space propulsion systems. Scheme 1. Network of polyimide aerogels crosslinked with deifferent poly(maleic anhydride).

cross-link↗

NASA NTRS2014

Synthesis, Processing, and Characterization of Inorganic-Organic Hybrid Cross-Linked Silica, Organic Polyimide, and Inorganic Aluminosilicate Aerogels

As aerospace applications become ever more demanding, novel insulation materials with lower thermal conductivity, lighter weight and higher use temperature are required to fit the aerospace application needs. Having nanopores and high porosity, aerogels are superior thermal insulators, among other things. The use of silica aerogels in general is quite restricted due to their inherent fragility, hygroscopic nature, and poor mechanical properties, especially in extereme aerospace environments. Our research goal is to develop aerogels with better mechanical and environmental stability for a variety of aeronautic and space applications including space suit insulation for planetary surface missions, insulation for inflatable structures for habitats, inflatable aerodynamic decelerators for entry, descent and landing (EDL) operations, and cryotank insulation for advance space propulsion systems. Different type of aerogels including organic-inorganic polymer reinforced (hybrid) silica-based aerogels, polyimide aerogels and inorganic aluminosilicate aerogels have been developed and examined.

Insulation materials↗

NASA NTRS2015

Feasibility of Dynamic Stability Measurements of Planetary Entry Capsules Using MSBS

The feasibility of conducting dynamic stability testing of planetary entry capsules at low supersonic Mach numbers using a Magnetic Suspension and Balance System (MSBS) is reviewed. The proposed approach would employ a spherical magnetic core, exert control in three degrees-of-freedom (i.e. x, y, z translations) and allow the model to freely rotate in pitch, yaw, and roll. A proof-of-concept system using an existing MSBS electromagnet array in a subsonic wind tunnel is described, with future potential for development of a new system for a supersonic wind tunnel.

Britcher, Colin↗

NASA NTRSDate not supplied

Feasibility of Additive Manufacturing for Thermal Protection Systems

Thermal Protection Systems (TPS) use advanced materials to protect vehicles from aerodynamic heating during atmospheric entry. Manufacturing of these composite materials is often very time consuming and labor-intensive. Leveraging the additive manufacturing FDM (Fused Deposition Modeling) process enables NASA to design and manufacture advanced ablative TPS materials while reducing manufacturing time and cost. Since additive manufacturing is an automated process, it ensures part consistency over the entire heat shield area. The purpose for this presentation will be three-fold. 1) Introduce novel low-density ablative materials capable of utilizing additive manufacturing capabilities 2) show feasibility of additively manufacturing TPS coupons using the downselected TPS materials 3) Side by side comparison of high temperature test results for printable paste and state of the art low-density ablators

T. Boghozian↗

NASA NTRS2020

Aerocapture as an Enhancing Option for Ice Giants Missions

Investigation of Uranus and Neptune, via orbiter and atmospheric probes, is required to answer pressing science questions that have been raised in previous Decadal Surveys. As the Ice Giants are the farthest planets from Earth, traditional fully-propulsive orbit insertion missions would require a large amount of propellant, leaving less mass for the scientific payload; additionally, transit time to the planetary bodies near 13-15 years. Aerocapture uses aerodynamic forces generated by flight within a planetary atmosphere to decelerate and achieve orbit insertion. Although, aerocapture has not been used in the past, recent developments in thermal protection systems, guidance and control, and navigation capabilities enable the use of rigid, heritage entry vehicle configurations already flown at other planetary bodies for Ice Giants aerocapture. With the addition of these recent capabilities, aerocapture can robustly deliver spacecraft to Ice Giant orbits, while substantially increasing on-orbit payload mass (more than 40%) and reducing the transit time by 2-5 years (15-30%) relative to fully-propulsive orbit insertion.

Soumyo Dutta↗

NASA NTRSDate not supplied

Neptune Odyssey Mission and Entry Descent Trajectory Design

Neptune is a prime destination for future exploration missions. This study designed the mission concept including the Flagship-class orbiter and atmospheric probe to the Neptune-Triton system. The results of this study will be used as the Decadal Survey considers on NASA’s planetary science priorities from 2022-2032.This poster will focus on the design of the entry and descent sequence for the atmospheric probe.

A Pensado↗

NASA NTRS2019

Development of OCSS In-Suit Urine Collection and Removal System for Cabin Depressurization Scenario

NASA is developing a waste management system for use in a pressurizable space suit for future Orion missions. Driven by Orion's cabin depress operational scenario, specific life support equipment is needed for crew survival. Immediate life-sustaining resources can be provided by the Orion launch and entry suit as a pressurizable safe haven. Before long, though, the crew would also need an appropriate waste management system to maintain their crew health in a confined environment, especially over multiple days. Long-duration waste management hardware for use with a space suit has not been designed or utilized since the Apollo program, and there are numerous technical challenges associated with its implementation. In conjunction both NASA's Orion Crew Survival Systems (OCSS) and Omni Medical Systems are addressing such challenges through their on-going hardware design efforts to support future Orion missions. This paper details some of the initial design and testing efforts that have been completed while discussing the major challenges that have arisen in the process.

Harvie, Mark↗

NASA NTRS1984

Space Shuttle separate-surface control-system study

A control system concept is presented that produces proportional control of yaw moment for the space shuttle from early entry to Mach 2 with only software modifications of the vehicle. It uses separate deflections of the inboard and outboard elevon surfaces and is evaluated, by determining the maximum static yawing moment available by considering the deflection limits of the elevon surfaces. A proportional moment slightly in excess of that produced by the most effective reaction control system (RCS) jet for yaw control can be obtained. In addition to the static moment study, a control law is designed which is intended to produce desired flying qualities.

Brown, L. W.↗

DOE OSTI2014

Modular cathode assemblies and methods of using the same for electrochemical reduction

Modular cathode assemblies are useable in electrolytic reduction systems and include a basket through which fluid electrolyte may pass and exchange charge with a material to be reduced in the basket. The basket can be divided into upper and lower sections to provide entry for the material. Example embodiment cathode assemblies may have any shape to permit modular placement at any position in reduction systems. Modular cathode assemblies include a cathode plate in the basket, to which unique and opposite electrical power may be supplied. Example embodiment modular cathode assemblies may have standardized electrical connectors. Modular cathode assemblies may be supported by a top plate of an electrolytic reduction system. Electrolytic oxide reduction systems are operated by positioning modular cathode and anode assemblies at desired positions, placing a material in the basket, and charging the modular assemblies to reduce the metal oxide.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Modular cathode assemblies and methods of using the same for electrochemical reduction

25 ENERGY STORAGE↗

DOE OSTI2016

SU-F-T-234: Quality Improvements in the Electronic Medical Record of Patients Treated with High Dose-Rate Brachytherapy

Purpose: To improve workflow efficiency and patient safety by assessing the quality control documentation for HDR brachytherapy within our Electronic Medical Record System (Mosaiq). Methods: A list of parameters based on NRC regulations, our quality management program (QMP), recommendations of the ACR and the American Brachytherapy Society, and HDR treatment planning risks identified in our previous FMEA study was made. Next, the parameter entries were classified according to the type of data input—manual, electronic, or both. Manual entry included the electronic Brachytherapy Treatment Record (BTR) and pre-treatment Mosaiq Assessments list. Oncentra Treatment Reports (OTR) from the Oncentra Treatment Control System constituted the electronic data. The OTR includes a Pre-treatment Report for each fraction, and a Treatment Summary Report at the completion of treatment. Each entry was then examined for appropriateness and completeness of data; adjustments and additions as necessary were then made. Results: Ten out of twenty-one recorded treatment parameters were identified to be documented within both the BTR and OTR. Of these ten redundancies, eight were changed from recorded values to a simple checklist in the BTR to avoid recording errors. The other redundancies were kept in both documents due to their value to ensuring patient safety. An edit was made to the current BTR quality assessment; this change revises the definition of a medical event in accordance with ODH Regulation 3701:1-58-101. One addition was made to the current QMP documents regarding HDR. This addition requires a physician to be present through the duration of HDR treatment in accordance with ODH Regulation 3701:1-58-59; Paragraph (F); Section (2); Subsection (a). Conclusion: Careful examination of HDR documentation that originates from different sources can help to improve the accuracy and reliability of the documents. In addition, there may be a small improvement in efficiency due to elimination of unnecessary redundancies.

60 APPLIED LIFE SCIENCES↗

NASA NTRS2024

Crew Health and Performance Integrated Data Architecture (CHP-IDA) Project

BACKGROUND: Future Human Exploration missions introduce a new paradigm as crews move further from the resupply and near real-time ground support typical of Low Earth Orbit missions today. Without immediate support from ground-based personnel, exploration crews will be more reliant on inflight data and technology to respond to emergencies and anomalies. A data architecture to support a new generation of technologies, employing advanced analytical and predictive modeling techniques, is needed to enable crew autonomy. OVERVIEW: The Crew Health and Performance Integrated Data Architecture (CHP-IDA) project funded by NASA’s Exploration Medical Integrated Product Team (XMIPT) is laying a foundation for future in-flight informatics by providing a back-end architecture for collecting, storing, and integrating multiple sources of data generated by and around the crew. CHP-IDA provides a platform for common data models and Application Programming Interfaces to access, integrate, process, and display CHP data (e.g., environmental, exercise, medical, sleep, performance, etc.). This will facilitate the increased situation awareness and decision support required by the crew and remote support of exploration missions. This presentation will describe the currently ongoing effort to develop and evaluate a path-to-flight concept of the CHP-IDA software and its core capabilities. Current integrations will be discussed, including analytics for Extravehicular Activity metabolic rate and data ingestion from a multi-functional integrated medical device. The presentation will also provide examples of scenarios used to demonstrate the CHP-IDA through human-in-the-loop test bed activities as well as examples of appropriate system performance metrics. DISCUSSION: Today, in-flight data is often siloed, unsynchronized, and largely inaccessible in real time. Many data sets require manual entry and/or data transfer between vehicles and the ground. These issues contribute to risks in supporting exploration medical capabilities. The CHP-IDA is a back-end data system providing core capabilities needed for timely and meaningful data insights across CHP domains to crew and remote personnel to enable increased crew autonomy. Future work includes collaboration with additional CHP domains, new technology integrations, and further demonstrations of the IDA within different vehicle and communication latency contexts. LEARNING OBJECTIVES 1. The audience will understand that the CHP-IDA is a back-end system, providing a platform to facilitate access, promote decision tools, and provide meaningful insights to crew and to remote stakeholders during exploration missions. 2. The audience will gain insight into human-centered research and activities used to discover CHP domain data needs and pain points and how this information is used to guide development of the IDA.

Exploration↗

NASA NTRS1980

Thermodynamic performance testing of the orbiter flash evaporator system

System level testing of the space shuttle orbiter's development flash evaporator system (FES) was performed in a thermal vacuum chamber capable of simulating ambient ascent, orbital, and entry temperature and pressure profiles. The test article included the evaporator assembly, high load and topping exhaust duct and nozzle assemblies, and feedwater supply assembly. Steady state and transient heat load, water pressure/temperature and ambient pressure/temperature profiles were imposed by especially designed supporting test hardware. Testing in 1978 verified evaporator and duct heater thermal design, determined FES performance boundaries, and assessed topping evaporator plume characteristics. Testing in 1979 combined the FES with the other systems in the orbiter active thermal control subsystem (ATCS). The FES met or exceeded all nominal and contingency performance requirements during operation with the integrated ATCS. During both tests stability problems were encountered during steady state operations which resulted in subsequent design changes to the water spray nozzle and valve plate assemblies.

Jaax, J. R.↗

NASA NTRS2014

Zephyr: A Landsailing Rover for Venus

With an average temperature of 450C and a corrosive atmosphere at a pressure of 90 bars, the surface of Venus is the most hostile environment of any planetary surface in the solar system. Exploring the surface of Venus would be an exciting goal, since Venus is a planet with significant scientific mysteries, and interesting geology and geophysics. Technology to operate at the environmental conditions of Venus is under development. A rover on the surface of Venus with capability comparable to the rovers that have been sent to Mars would push the limits of technology in high-temperature electronics, robotics, and robust systems. Such a rover would require the ability to traverse the landscape on extremely low power levels. We have analyzed an innovative concept for a planetary rover: a sail-propelled rover to explore the surface of Venus. Such a rover can be implemented with only two moving parts; the sail, and the steering. Although the surface wind speeds are low (under 1 m/s), at Venus atmospheric density even low wind speeds develop significant force. Under funding by the NASA Innovative Advanced Concepts office, a conceptual design for such a rover has been done. Total landed mass of the system is 265 kg, somewhat less than that of the MER rovers, with a 12 square meter rigid sail. The rover folds into a 3.6 meter aeroshell for entry into the Venus atmosphere and subsequent parachute landing on the surface. Conceptual designs for a set of hightemperature scientific instruments and a UHF communication system were done. The mission design lifetime is 50 days, allowing operation during the sunlit portion of one Venus day. Although some technology development is needed to bring the high-temperature electronics to operational readiness, the study showed that such a mobility approach is feasible, and no major difficulties are seen.

rover↗

NASA NTRSDate not supplied

Thermal Protection Materials and Systems at NASA Ames Research Center

Thermal Protection Systems (TPS) are critical for enabling NASA missions involving high-speed atmospheric flight where the entries usually include descending into the atmosphere followed by a trajectory that aims to burn off energy and result in a controlled landing. NASA Ames focuses on qualifying and certifying TPS for current missions, sustaining TPS for future missions, and developing new TPS for upcoming missions where a heritage solution is not viable. More recently there is also a focus on advancing and transferring technologies that can benefit both commercial and government space needs.Developing mature thermal protection systems is a lengthy process involving advanced tools, extensive research, and testing. Design and analysis tools are used to predict aerothermal environments, aid the design of test and flight hardware, and support the testing for the thermal/mechanical response of thermal protection systems. More recently, advances in computational methods help reduce the time and cost of technological advances, aid in optimized material architecture design, and improve material properties and performance. While high-enthalpy testing that simulates the conditions of space flight remains essential for the evaluation and development of TPS materials, computational tools are already showing promise in reducing the need for widespread testing and can help fast-trackthe design cycle.With the exploration of new destinations EDL instrumentation remains an important element of the heatshield and NASA Ames and partners have developed and delivered instrumentation flight hardware in support of recent Mars missions,including Mars Science Lab (MSL) and Mars 2020 (M2020),as well as Artemis Orion. Sensors installed on the heatshield and backshell of spacecraft provide coveted information about the aerodynamic and aerothermal environment during entry.Overthe years NASA Ames has brought several reusable and ablative TPS materials to a level of readiness to hand off to missions and the Thermal Protection Materials branch continues to serve as a TPS steward for the agency.

Thermal protection materials↗

NASA NTRS1971

Combined study program. Volume 5 - Direct entry accumulator cell molecular beam ion source Final report

Molecular beam ion source for spacecraft mass spectrometer atmospheric sensor system

Rotheram, M.↗

NASA NTRS1990

Effectiveness of the Space Shuttle anti-exposure system in a cold water environment

The purpose of this study was to evaluate the NASA Space Shuttle launch entry suit (LES) and raft for 24 h of protection against cold water immersion. Two configurations, the LES and the LES with raft (LES/r) were evaluated for antiexposure protection. Conditions were selected to simulate worst-case water and air temperatures along projected Space Shuttle ground tracks; i.e., water temperatures = 4.4 C, air temperature = 5.6 C, 1-foot waves (chop), and constant spray. Four males 31-44 years of age and one 32-year-old female were studied once in each configuration. Trials with and without a raft were scheduled for up to 24 and 6 h, respectively. Mean LES trial durations were 150 + or - 9 min and final rectal temperature (FRT) = 36.5 + or - 0.3 C. Mean LES/r trial durations were 398 + or - 126 min and FRT = 35.6 + or - 0.4 C. LES and LES/r trials were terminated for reaching FRT = 35.0 C or subject-requested termination due to discomfort. The longest LES and LES/r trials were terminated due to subject discomfort. Although not achieving the desired durations, the LES and LES/r did prove capable of protecting individuals, respectively, for up to 3 and 13.5 h. Since the longest runs were terminated due to subjective tolerance, actual survival times greater than 3 and 13.5 h could be expected.

Bagian, James P.↗

NASA NTRS1991

Guidance and control analysis of the entry of a lifting body personnel launch vehicle

NASA is currently involved in definition studies of a Personnel Launch System (PLS) that could be used to transport people to and from low-earth orbit. This vehicle would serve both to complement the Space Shuttle and to provide alternative access to space in the event the Space Shuttle fleet were unavailable for a prolonged period. The PLS would consist of a manned spacecraft launched by an expendable vehicle, e.g., Titan 4. One promising candidate for the manned component of the PLS is the NASA Langley Research Center HL-20 lifting body. Many studies are currently underway to assess this vehicle, and one of the main areas of study is the development of the capability to successfully enter, glide to the landing site, and land. To provide this capability, guidance and control algorithms have been developed, incorporated into a six-degree-of-freedom simulation, and evaluation in the presence of off-nominal atmospheric conditions, consisting of both density variations and steady-state winds. In addition, the impact of atmospheric turbulence was examined for the portion of flight from Mach 3.5 to touchdown. This analysis showed that the vehicle remained controllable and could successfully land even in the presence of off-nominal atmospheric conditions.

Powell, Richard W.↗