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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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NASA NTRS1993

The AC-120: The advanced commercial transport

The main objective of this design was to fulfill a need for a new airplane to replace the aging 100 to 150 passenger, 1500 nautical mile range aircraft such as the Douglas DC9 and Boeing 737-100 airplanes. After researching the future aircraft market, conducting extensive trade studies, and analysis on different configurations, the AC-120 Advanced Commercial Transport final design was achieved. The AC-120's main design features include the incorporation of a three lifting surface configuration which is powered by two turboprop engines. The AC-120 is an economically sensitive aircraft which meets the new FM Stage Three noise requirements, and has lower NO(x) emissions than current turbofan powered airplanes. The AC-120 also improves on its contemporaries in passenger comfort, manufacturing, and operating cost.

Duran, David↗
NASA NTRS2007

The MSFC Systems Engineering Guide: An Overview and Plan

As systems and subsystems requirements become more complex in the pursuit of the exploration of space, advanced technology will demand and require an integrated approach to the design and development of safe and successful space vehicles and there products. System engineers play a vital and key role in transforming mission needs into vehicle requirements that can be verified and validated. This will result in a safe and cost effective design that will satisfy the mission schedule. A key to successful vehicle design within systems engineering is communication. Communication, through a systems engineering infrastructure, will not only ensure that customers and stakeholders are satisfied but will also assist in identifying vehicle requirements; i.e. identification, integration and management. This vehicle design will produce a system that is verifiable, traceable, and effectively satisfies cost, schedule, performance, and risk throughout the life-cycle of the product. A communication infrastructure will bring about the integration of different engineering disciplines within vehicle design. A system utilizing these aspects will enhance system engineering performance and improve upon required activities such as Development of Requirements, Requirements Management, Functional Analysis, Test, Synthesis, Trade Studies, Documentation, and Lessons Learned to produce a successful final product. This paper will describe the guiding vision, progress to date and the plan forward for development of the Marshall Space Flight Center (MSFC) Systems Engineering Guide (SEG), a virtual systems engineering handbook and archive that will describe the system engineering processes that are used by MSFC in the development of complex systems such as the Ares launch vehicle. It is the intent of this website to be a "One Stop Shop" for our systems engineers that will provide tutorial information, an overview of processes and procedures and links to assist system engineering with guidance and references, and provide an archive of systems engineering artifacts produced by the many NASA projects developed and managed by MSFC over the years.

Shelby, Jerry A.↗
NASA NTRS2009

Ares V: Shifting the Payload Design Paradigm

NASA's Ares V heavy-lift cargo launch vehicle is being designed send more crew and cargo to more places on the lunar surface than the 1960s-era Apollo program and provide ongoing support to a permanent lunar outpost. In addition to that role, however, its unmatched mass and volume capability represent a global asset for exploration, science, and commerce. The Ares V also is an enabler of a large class of space missions not thought possible by scientists and engineers since the Saturn V program ended over 30 years ago. Compared to current systems, it will offer approximately 5 times the mass and volume to most orbits and locations. This should allow prospective mission planners to build robust payloads with margins that are 3 to 5 times the industry norm. The space inside the planned payload shroud has enough usable volume to launch the volumetric equivalent of approximately 10 Apollo Lunar Excursion Modules or approximately 5 equivalent Hubble Space Telescopes. This mass and volume capability to Low Earth Orbit enables a host of new scientific and observation platforms, such as telescopes, satellites, planetary and solar missions, as well as being able to provide the lift for future large in-space infrastructure missions, such as space based power and mining, Earth asteroid defense, propellant depots, etc. The Ares V team is engaging the potential payload community now, 2-3 years before System Requirements Review, in order to better understand the potential limitations and or additional requirements that could be added to the Ares V from the mission planning community. If a viable mission is determined and added to the Ares V as a design case, tradeoffs will be conducted to determine if other mission design requirements can be included in the system. Multiple shroud options for the Ares V have been analyzed to identify their impact on performance. Ares V is in a conceptual design stage prior to a formal design phase. The initial concept for the cargo launch vehicle (CaLV) that would later be dubbed "Ares V" was produced by the Exploration Systems Architecture Study in 2005. Since then, it has evolved through hundreds of concepts. The current point-of-departure (POD) concept was approved during the Lunar Capabilities Concept Review/Ares V Mission Concept Review in June 2008. This reference concept serves as a starting point for a renewed set of design trades and detailed analysis into its interaction with the other components of the Constellation architecture and existing launch infrastructure. This paper will discuss the Ares V design evolution, the most recent point-of-departure concept, and its capabilities to support future science missions.

Summrall, Phil↗
NASA NTRS2009

Ares V Overview and Status

As part of NASA s Constellation Program to resume exploration beyond low Earth orbit (LEO), the Ares V heavy-lift cargo launch vehicle as currently conceived will be able to send more crew and cargo to more places on the Moon than the Apollo Program Saturn V. (Figure 1) It also has unprecedented cargo mass and volume capabilities that will be a national asset for science, commerce, and national defense applications. Compared to current systems, it will offer approximately five times the mass and volume to most orbits and locations. The Columbia space shuttle accident, the resulting investigation, the Vision for Space Exploration, and the Exploration Systems Architecture Study (ESAS) broadly shaped the Constellation architecture. Out of those events and initiatives emerged an architecture intended to replace the space shuttle, complete the International Space Station (ISS), resume a much more ambitious plan to explore the moon as a stepping stone to other destinations in the solar system. The Ares I was NASA s main priority because of the goal to retire the Shuttle. Ares V remains in a concept development phase, evolving through hundreds of configurations. The current reference design was approved during the Lunar Capabilities Concept Review/Ares V Mission Concept Review (LCCR/MCR) in June 2008. This reference concept serves as a starting point for a renewed set of design trades and detailed analysis into its interaction with the other components of the Constellation architecture and existing launch infrastructure. In 2009, the Ares V team was heavily involved in supporting the Review of U.S. Human Space Flight Plans Committee. Several alternative designs for Ares V have been supplied to the committee. This paper will discuss the origins of the Ares V design, the evolution to the current reference configuration, and the options provided to the review committee.

Creech, Steve↗
NASA NTRS2011

NASA Tech Briefs, August 2011

Topics covered include: Miniature, Variable-Speed Control Moment Gyroscope; NBL Pistol Grip Tool for Underwater Training of Astronauts; HEXPANDO Expanding Head for Fastener-Retention Hexagonal Wrench; Diagonal-Axes Stage for Pointing an Optical Communications Transceiver; Improvements in Speed and Functionality of a 670-GHz Imaging Radar; IONAC-Lite; Large Ka-Band Slot Array for Digital Beam-Forming Applications; Development of a 150-GHz MMIC Module Prototype for Large-Scale CMB Radiation; Coupling Between Waveguide-Fed Slot Arrays; PCB-Based Break-Out Box; Multiple-Beam Detection of Fast Transient Radio Sources; Router Agent Technology for Policy-Based Network Management; Remote Asynchronous Message Service Gateway; Automatic Tie Pointer for In-Situ Pointing Correction; Jitter Correction; MSLICE Sequencing; EOS MLS Level 2 Data Processing Software Version 3; DspaceOgre 3D Graphics Visualization Tool; Metallization for Yb14MnSb11-Based Thermoelectric Materials; Solvent/Non-Solvent Sintering To Make Microsphere Scaffolds; Enhanced Fuel-Optimal Trajectory-Generation Algorithm for Planetary Pinpoint Landing; Self-Cleaning Coatings and Materials for Decontaminating Field-Deployable Land and Water-Based Optical Systems; Separation of Single-Walled Carbon Nanotubes with DEP-FFF; Li Anode Technology for Improved Performance; Post-Fragmentation Whole Genome Amplification-Based Method; Microwave Tissue Soldering for Immediate Wound Closure; Principles, Techniques, and Applications of Tissue Microfluidics; Robotic Scaffolds for Tissue Engineering and Organ Growth; Stress-Driven Selection of Novel Phenotypes; Method for Accurately Calibrating a Spectrometer Using Broadband Light; Catalytic Microtube Rocket Igniter; Stage Cylindrical Immersive Display; Vacuum Camera Cooler; Atomic Oxygen Fluence Monitor; Thermal Management Tools for Propulsion System Trade Studies and Analysis; Introduction to Physical Intelligence; Technique for Solving Electrically Small to Large Structures for Broadband Applications; Accelerated Adaptive MGS Phase Retrieval; Large Eddy Simulation Study for Fluid Disintegration and Mixing; Tropospheric Correction for InSAR Using Interpolated ECMWF Data and GPS Zenith Total Delay; Technique for Calculating Solution Derivatives With Respect to Geometry Parameters in a CFD Code; Acute Radiation Risk and BRYNTRN Organ Dose Projection Graphical User Interface; Probabilistic Path Planning of Montgolfier Balloons in Strong, Uncertain Wind Fields; Flight Simulation of ARES in the Mars Environment; Low-Outgassing Photogrammetry Targets for Use in Outer Space; Planning the FUSE Mission Using the SOVA Algorithm; Monitoring Spacecraft Telemetry Via Optical or RF Link; and Robust Thermal Control of Propulsion Lines for Space Missions.

Source record↗
NASA NTRS2014

Dual Fan Separator within the Universal Waste Management System

Since NASA's new spacecraft in development for both LEO and Deep Space capability have considerable crew volume reduction in comparison to the Space Shuttle, the need became apparent for a smaller commode. In response the Universal Waste Management System (UWMS) was designed, resulting in an 80% volume reduction from the last US commode, while enhancing performance. The ISS WMS and previous shuttle commodes have a fan supplying air flow to capture feces and a separator to capture urine and separate air from the captured air/urine mixture. The UWMS combined both rotating equipment components into a single unit, referred to at the Dual Fan Separator (DFS). The combination of these components resulted in considerable packaging efficiency and weight reduction, removing inter-component plumbing, individual mounting configurations and required only a single motor and motor controller, in some of the intended UWMS platform applications the urine is pumped to the ISS Urine Processor Assembly (UPA) system. It requires the DFS to include less than 2.00% air inclusion, by volume, in the delivered urine. The rotational speed needs to be kept as low as possible in centrifugal urine separators to reduce air inclusion in the pumped fluid, while fans depend on rotational speed to develop delivered head. To satisfy these conflicting requirements, a gear reducer was included, allowing the fans to rotate at a much higher speed than the separator. This paper outlines the studies and analysis performed to develop the DFS configuration. The studies included a configuration trade study, dynamic stability analysis of the rotating bodies and a performance analysis of included labyrinth seals. NASA is considering a program to fly the UWMS aboard the ISS as a flight experiment. The goal of this activity is to advance the Technical Readiness Level (TRL) of the DFS and determine if the concept is ready to be included as part of the flight experiment deliverable.

Stapleton, Tom↗
NASA NTRS2014

LARES Mission: Separation and Retention Subsystem

As part of the Lares (LAser RElativity Satellite) mission, an all-Italian scientific mission launched with the Vega maiden flight in February 2012, a mechanical separation and retention subsystem (SSEP) has been developed to retain the LARES satellite during launch and release it in the final orbit. The design flow was based on the identification of the driving requirements and critical areas to guide the trade-off, design, analysis and test activities. In particular, the SSEP had to face very high environmental loads and to minimize the contact areas with the satellite that had a spherical shape. The test activity overview is provided.

Bursi, Alessandro↗
NASA NTRSDate not supplied

Key Performance Parameters for an Operational CIS-Lunar NTP Vehicle

Nuclear Thermal Propulsion (NTP) is in active development by NASA and DARPA. This paper presents an investigation into the effects of different values of key performance parameters (KPPs) of an NTP engine in the context of payload delivery missions between Earth and Lunar orbits. The high Isp afforded by NTP combined with the relatively large engine mass is best applied to missions where the payload mass is large and required ΔV high. Two missions considered are the round-trip Earth to Moon tug and a NRHO to low Lunar orbit tug. Chemical propulsion vehicles can generally achieve higher propellant mass fractions, similar payload mass and similar ΔV performance on these missions. When re-use of the vehicle is considered, the reduced propellant mass required by an NTP vehicle begins to add up over multiple refilling launches and trades more favorably. Analysis illustrates the impact of variation in NTP engine performance values, especially Isp, engine mass and thrust, on performance and the comparison to chemical propulsion. NTP transient and cooldown effects on the vehicle performance are examined. A variety of launch vehicles and hydrogen and ammonia NTP propellants are included in the analyses, and cryogenic fluid management system effects are accounted for.

NTP↗
DOE OSTI2020

Development and Application of a Risk Analysis Toolkit for Plant Resources Optimization

This report summarizes the R&D activities of the Risk Informed Asset Management (RIAM) project during fiscal year 2020 (FY20). This project focuses on the development of methods designed to optimize plant operations (e.g., maintenance/replacement schedule, optimal maintenance posture) provided system/component health/cost data. This project development lives in cooperation with the Plant Health Management (PHM) project which focuses on the development of methods that integrate component health data and propagate such information at the system level to evaluate most relevant sources of risk. This year’s activities for the RIAM project focused on the continuation of schedule optimization algorithms developed in FY19. While in FY19 we focused on both deterministic and stochastic capital budgeting methods, in FY20 we moved forward by implementing two versions of schedule optimization methods. The first one reformulates the capital budgeting problem in a distributionally robust form which allows the user to rely on data directly rather than proposing a distribution from the data itself. The second version reformulates the capital budgeting explicitly using risk measures as variables to maximize/minimize. Lastly, we focused on the development of methods designed to identify the optimal maintenance posture based on the Pareto Frontier analysis. Rather than performing a tradeoff analysis (i.e., identify the absolute best posture), the Pareto Frontier analysis performs a trade space exploration approach (i.e., identify value and costs of several postures and have the analyst perform the task of imposing desired value and cost constraints). This is performed by identifying maintenance postures that maximize value (e.g., system availability) and minimize operational costs, i.e., the Pareto frontier in a value-cost trade space.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS1992

Cycle O(CY1991) NLS trade studies and analyses report. Book 2, part 2: Propulsion

This report documents the propulsion system tasks performed in support of the National Launch System (NLS) Cycle O preliminary design activities. The report includes trades and analyses covering the following subjects: (1) Maximum Tank Stretch Study; (2) No LOX Bleed Performance Analysis; (3) LOX Bleed Trade Study; (4) LO2 Tank Pressure Limits; (5) LOX Tank Pressurization System Using Helium; (6) Space Transportation Main Engine (STME) Heat Exchanger Performance; (7) LH2 Passive Recirculation Performance Analysis; (8) LH2 Bleed/Recirculation Study; (9) LH2 Tank Pressure Limits; and (10) LH2 Pressurization System. For each trade study an executive summary and a detailed trade study are provided. For the convenience of the reader, a separate section containing a compilation of only the executive summaries is also provided.

Cronin, R.↗
NASA NTRS2012

Getting a Cohesive Answer from a Common Start: Scalable Multidisciplinary Analysis through Transformation of a Systems Model

One of the challenges of systems engineering is in working multidisciplinary problems in a cohesive manner. When planning analysis of these problems, system engineers must trade between time and cost for analysis quality and quantity. The quality often correlates with greater run time in multidisciplinary models and the quantity is associated with the number of alternatives that can be analyzed. The trade-off is due to the resource intensive process of creating a cohesive multidisciplinary systems model and analysis. Furthermore, reuse or extension of the models used in one stage of a product life cycle for another is a major challenge. Recent developments have enabled a much less resource-intensive and more rigorous approach than hand-written translation scripts between multi-disciplinary models and their analyses. The key is to work from a core systems model defined in a MOF-based language such as SysML and in leveraging the emerging tool ecosystem, such as Query/View/Transformation (QVT), from the OMG community. SysML was designed to model multidisciplinary systems. The QVT standard was designed to transform SysML models into other models, including those leveraged by engineering analyses. The Europa Habitability Mission (EHM) team has begun to exploit these capabilities. In one case, a Matlab/Simulink model is generated on the fly from a system description for power analysis written in SysML. In a more general case, symbolic analysis (supported by Wolfram Mathematica) is coordinated by data objects transformed from the systems model, enabling extremely flexible and powerful design exploration and analytical investigations of expected system performance.

Operational QVT↗
NASA NTRS1989

Space biology initiative program definition review. Trade study 5: Modification of existing hardware (COTS) versus new hardware build cost analysis

The JSC Life Sciences Project Division has been directly supporting NASA Headquarters, Life Sciences Division, in the preparation of data from JSC and ARC to assist in defining the Space Biology Initiative (SBI). GE Government Services and Horizon Aerospace have provided contract support for the development and integration of review data, reports, presentations, and detailed supporting data. An SBI Definition (Non-Advocate) Review at NASA Headquarters, Code B, has been scheduled for the June-July 1989 time period. In a previous NASA Headquarters review, NASA determined that additional supporting data would be beneficial to determine the potential advantages in modifying commercial off-the-shelf (COTS) hardware for some SBI hardware items. In order to meet the demands of program implementation planning with the definition review in late spring of 1989, the definition trade study analysis must be adjusted in scope and schedule to be complete for the SBI Definition (Non-Advocate) Review. The relative costs of modifying existing commercial off-the-shelf (COTS) hardware is compared to fabricating new hardware. An historical basis for new build versus modifying COTS to meet current NMI specifications for manned space flight hardware is surveyed and identified. Selected SBI hardware are identified as potential candidates for off-the-shelf modification and statistical estimates on the relative cost of modifying COTS versus new build are provided.

Jackson, L. Neal↗
NASA NTRS2013

Advanced Single-Aisle Transport Propulsion Design Options Revisited

Future propulsion options for advanced single-aisle transports have been investigated in a number of previous studies by the authors. These studies have examined the system level characteristics of aircraft incorporating ultra-high bypass ratio (UHB) turbofans (direct drive and geared) and open rotor engines. During the course of these prior studies, a number of potential refinements and enhancements to the analysis methodology and assumptions were identified. This paper revisits a previously conducted UHB turbofan fan pressure ratio trade study using updated analysis methodology and assumptions. The changes incorporated have decreased the optimum fan pressure ratio for minimum fuel consumption and reduced the engine design trade-offs between minimizing noise and minimizing fuel consumption. Nacelle drag and engine weight are found to be key drivers in determining the optimum fan pressure ratio from a fuel efficiency perspective. The revised noise analysis results in the study aircraft being 2 to 4 EPNdB (cumulative) quieter due to a variety of reasons explained in the paper. With equal core technology assumed, the geared engine architecture is found to be as good as or better than the direct drive architecture for most parameters investigated. However, the engine ultimately selected for a future advanced single-aisle aircraft will depend on factors beyond those considered here.

Guynn, Mark D.↗
NASA NTRS2014

Dual Fan Separator within the Universal Waste Management System

Since NASA's new spacecraft in development for both LEO and Deep Space capability have considerable crew volume reduction in comparison to the Space Shuttle, it is clear that NASA requires a smaller and less expensive commode. The UTAS Universal Waste Management System (UWMS) was designed to address these new constraints, resulting in an 80% volume reduction in the cabin while enhancing performance. Whereas all of the current space commodes use air flow to capture both urine and feces and separate air from the captured air/urine mixture, the UWMS commode and urine fans and the urine separator were combined into a single unit. This unit enables use of a single motor and motor controller, which provides considerable packaging and weight efficiency. In some of the intended platform applications for the UWMS, the urine is pumped to a water reclamation system. The ISS Urine Processor Assembly (UPA) system requires delivered urine to include less than 0.25% air inclusion. Air inclusion in centrifugal urine separators is greatly dependent on its rotational speed. To satisfy this requirement, a gear reducer was included, allowing the fans to rotate at a much higher speed than the separator. This new design, the Dual Fan Separator (DFS) has been designed, prototyped and tested. This paper will outline the studies and analysis performed to develop the design configuration for testing. The studies included a configuration trade study, dynamic stability analysis of the rotating bodies and a performance analysis of included labyrinth seals. NASA is considereing a program to fly the UWMS aboard the ISS as a flight experiment. The goal of the design activity is to elevate the Technical Readiness Level (TRL) of the Dual Fan Separator and determine if the concept is ready to be included in flight experiment deliverable.

Stapleton, Tom↗
NASA NTRS2014

Coupled Solid Rocket Motor Ballistics and Trajectory Modeling for Higher Fidelity Launch Vehicle Design

Multi-stage launch vehicles with solid rocket motors (SRMs) face design optimization challenges, especially when the mission scope changes frequently. Significant performance benefits can be realized if the solid rocket motors are optimized to the changing requirements. While SRMs represent a fixed performance at launch, rapid design iterations enable flexibility at design time, yielding significant performance gains. The streamlining and integration of SRM design and analysis can be achieved with improved analysis tools. While powerful and versatile, the Solid Performance Program (SPP) is not conducive to rapid design iteration. Performing a design iteration with SPP and a trajectory solver is a labor intensive process. To enable a better workflow, SPP, the Program to Optimize Simulated Trajectories (POST), and the interfaces between them have been improved and automated, and a graphical user interface (GUI) has been developed. The GUI enables real-time visual feedback of grain and nozzle design inputs, enforces parameter dependencies, removes redundancies, and simplifies manipulation of SPP and POST's numerous options. Automating the analysis also simplifies batch analyses and trade studies. Finally, the GUI provides post-processing, visualization, and comparison of results. Wrapping legacy high-fidelity analysis codes with modern software provides the improved interface necessary to enable rapid coupled SRM ballistics and vehicle trajectory analysis. Low cost trade studies demonstrate the sensitivities of flight performance metrics to propulsion characteristics. Incorporating high fidelity analysis from SPP into vehicle design reduces performance margins and improves reliability. By flying an SRM designed with the same assumptions as the rest of the vehicle, accurate comparisons can be made between competing architectures. In summary, this flexible workflow is a critical component to designing a versatile launch vehicle model that can accommodate a volatile mission scope.

Ables, Brett↗
NASA NTRS1972

A study of system requirements for Phobos/Deimos missions. Volume 4: Phase 3 results, combined missions to Mars and its satellites

Combined missions to Mars and Phobos/Deimos were considered in relation to large scientific returns at a low total cost. A matrix of all feasible major combined mission concepts was compiled. The most promising approach was selected from which a nominal mission profile was developed. A systems analysis was performed to trade off performance, configuration, and cost characteristics of candidate mission concepts. Configuration and subsystem optimization analysis were then conducted from which a baseline and an alternate program were selected. Program schedules and cost estimates were prepared for the recommended and alternate program.

Source record↗
NASA NTRS2005

Terrestrial Planet Finder Coronagraph Observatory summary

Creating an optical space telescope observatory capable of detecting and characterizing light from extra-solar terrestrial planets poses technical challenges related to extreme wavefront stability. The Terrestrial Planet Finder Coronagraph design team has been developing an observatory based on trade studies, modeling and analysis that has guided us towards design choices to enable this challenging mission. This paper will describe the current flight baseline design of the observatory and the trade studies that have been performed. The modeling and analysis of this design will be described including predicted performance and the tasks yet to be done.

space↗
NASA NTRS1986

Orbital transfer vehicle concept definition and system analysis study, 1985. Volume 3: System and program trades

The key system and program trade studies performed to arrive at a preferred Orbital Transfer Vehicle (OTV) system concept and evolutionary approach to the acquisition of the requisite capabilites is documented. These efforts were expanded to encompass a Space Transportation Architecture Study (STAS) mission model and recommended unmanned cargo vehicle. The most important factors affecting the results presented are the mission model requirements and selection criteria. The reason for conducting the OTV concept definition and system analyses study is to select a concept and acquisition approach that meets a delivery requirement reflected by the mission model.

Nelson, James H.↗