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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Exergy Efficiency of Interplanetary Transfer Vehicles

In order to optimize systems, systems engineers require some sort of measure with which to compare vastly different system components. One such measure is system exergy, or the usable system work. Exergy balance analysis models provide a comparison of different system configurations, allowing systems engineers to compare different systems configuration options. This paper presents the exergy efficiency of several Mars transportation system configurations, using data on the interplanetary trajectory, engine performance, and vehicle mass. The importance of the starting and final parking orbits is addressed in the analysis, as well as intermediate hyperbolic escape and entry orbits within Earth and Mars' spheres of influence (SOIs). Propulsion systems analyzed include low-enriched uranium (LEU) nuclear thermal propulsion (NTP), high-enriched uranium (HEU) NTP, LEU methane (CH4) NTP, and liquid oxygen (LOX)/liquid hydrogen (LH2) chemical propulsion.

Owen, Sean T.↗
NASA NTRS2018

Exergy Efficiency of Interplanetary Transfer Vehicles

In order to optimize systems, systems engineers require some sort of measure with which to compare vastly different system components. One such measure is system exergy, or the usable system work. Exergy balance analysis models provide a comparison of different system configurations, allowing systems engineers to compare different systems configuration options. This paper presents the exergy efficiency of several Mars transportation system configurations, using data on the interplanetary trajectory, engine performance, and vehicle mass. The importance of the starting and final parking orbits is addressed in the analysis, as well as intermediate hyperbolic escape and entry orbits within Earth and Mars' spheres of influence (SOIs). Propulsion systems analyzed include low-enriched uranium (LEU) nuclear thermal propulsion (NTP), high-enriched uranium (HEU) NTP, LEU methane (CH4) NTP, and liquid oxygen (LOX)/liquid hydrogen (LH2) chemical propulsion.

Owen, Sean T.↗
NASA NTRS2002

Solar Electric Propulsion Vehicle Design Study for Cargo Transfer to Earth-moon L1

A design study for a cargo transfer vehicle using solar electric propulsion was performed for NASA's Revolutionary Aerospace Systems Concepts program. Targeted for 2016, the solar electric propulsion (SEP) transfer vehicle is required to deliver a propellant supply module with a mass of approximately 36 metric tons from Low Earth Orbit to the first Earth-Moon libration point (LL1) within 270 days. Following an examination of propulsion and power technology options, a SEP transfer vehicle design was selected that incorporated large-area (approx. 2700 sq m) thin film solar arrays and a clustered engine configuration of eight 50 kW gridded ion thrusters mounted on an articulated boom. Refinement of the SEP vehicle design was performed iteratively to properly estimate the required xenon propellant load for the out-bound orbit transfer. The SEP vehicle performance, including the xenon propellant estimation, was verified via the SNAP trajectory code. Further efforts are underway to extend this system model to other orbit transfer missions.

Sarver-Verhey, Timothy R.↗
NASA NTRS1979

Satellite Power System (SPS) concept definition study (exhibit C)

The major outputs of the study are the constructability studies which resulted in the definition of the concepts for satellite, rectenna, and satellite construction base construction. Transportation analyses resulted in definition of heavy-lift launch vehicle, electric orbit transfer vehicle, personnel orbit transfer vehicle, and intra-orbit transfer vehicle as well as overall operations related to transportation systems. The experiment/verification program definition resulted in the definition of elements for the Ground-Based Experimental Research and Key Technology plans. These studies also resulted in conceptual approaches for early space technology verification. The cost analysis defined the overall program and cost data for all program elements and phases.

Haley, G. M.↗
NASA NTRS1990

Final design of a space debris removal system

The objective is the removal of medium sized orbital debris in low Earth orbits. The design incorporates a transfer vehicle and a netting vehicle to capture the medium size debris. The system is based near an operational space station located at 28.5 degrees inclination and 400 km altitude. The system uses ground based tracking to determine the location of a satellite breakup or debris cloud. This data is unloaded to the transfer vehicle, and the transfer vehicle proceeds to rendezvous with the debris at a lower altitude parking orbit. Next, the netting vehicle is deployed, tracks the targeted debris, and captures it. After expending the available nets, the netting vehicle returns to the transfer vehicle for a new netting module and continues to capture more debris in the target area. Once all the netting modules are expended, the transfer vehicle returns to the space station's orbit, where it is resupplied with new netting modules from a space shuttle load. The new modules are launched by the shuttle from the ground, and the expended modules are taken back to Earth for removal of the captured debris, refueling, and repacking of the nets. Once the netting modules are refurbished, they are taken back into orbit for reuse. In a typical mission, the system has the ability to capture 50 pieces of orbital debris. One mission will take about six months. The system is designed to allow for a 30 degree inclination change on the outgoing and incoming trips of the transfer vehicle.

Carlson, Erika↗
NASA NTRS1993

Lunar transportation system

The University Space Research Association (USRA) requested the University of Minnesota Spacecraft Design Team to design a lunar transportation infrastructure. This task was a year long design effort culminating in a complete conceptual design and presentation at Johnson Space Center. The mission objective of the design group was to design a system of vehicles to bring a habitation module, cargo, and crew to the lunar surface from LEO and return either or both crew and cargo safely to LEO while emphasizing component commonality, reusability, and cost effectiveness. During the course of the design, the lunar transportation system (LTS) has taken on many forms. The final design of the system is composed of two vehicles, a lunar transfer vehicle (LTV) and a lunar excursion vehicle (LEV). The LTV serves as an efficient orbital transfer vehicle between the earth and the moon while the LEV carries crew and cargo to the lunar surface. Presented in the report are the mission analysis, systems layout, orbital mechanics, propulsion systems, structural and thermal analysis, and crew systems, avionics, and power systems for this lunar transportation concept.

Source record↗
NASA NTRS1980

SPS program review transportation perspective

The delivery of cargo and space workers to the SPS construction site requires the development of two different systems, one to handle large cargo deliveries and a smaller system to accommodate crew. The overall scenario of the transportation system is shown. Eight major elements comprise the transportation system: personnel launch vehicle (PLV) or shuttle; personnel orbital transfer vehicle (POTV); the heavy lift launch vehicle (HLLV); the electric orbital transfer vehicle (EOTV); intra orbit transfer vehicle (IOTV); LEO support facility; GEO support facility and a shuttle derived HLLV (SDHLLV) for supporting the early SPS Demonstration Program. The HLLV and EOTV represent the cargo carriers while the PLV and POTV represent the people carriers. The IOTV is utilized to ferry people and cargo modules over short distances in the vicinity of its station.

Wales, W. W., Jr.↗
NASA NTRS1984

A view of future technology needs for space transportation

This paper addresses an independent assessment of space transportation requirements within the NASA and Military Space Systems Technology Models. A critical examination is made of the system needs of the various flight elements with the models as compared to independent technology forecasts and possible technology deficiencies are discussed. These deficits impact the requisite developments needed for chemical propulsion, thermal protection systems, fuel cells, guidance, avionics and data processing for both launch vehicles and orbital transfer vehicles. Also addressed are potential alternative propellant technologies and their impact upon transfer vehicle systems. The primary focus of these anticipated technology developments will be to reduce operational costs, expand flexibility, and increase the payload capability of space transportation.

Gartrell, C. F.↗
NASA NTRS1984

Space station orbit selection

Architecture and operations with respect to a permanent manned space facility are being studied, and basic modules of such a space station could be in orbit by 1992. A manned space station in low-earth orbit (LEO) represents a transportation node between the Space Shuttle and orbital transfer vehicles which together comprise a total space transportation system. The present investigation has the objective to examine the trades between performance and operational requirements of a space transportation system which affect space station orbit selection. Factors influencing the trades and selection process include launch vehicle and orbital transfer vehicle (OTV) delivery performance, vehicle launch frequency and windows, station drag characteristics, drag-makeup propulsion, and minimum orbital lifetime requirements.

Talay, T. A.↗
NASA NTRS1991

In-Space Assembly and Construction Technology Project Summary: Infrastructure Operations Area of the Operations Technology Program

Viewgraphs describing the in-space assembly and construction technology project of the infrastructure operations area of the operation technology program are presented. Th objective of the project is to develop and demonstrate an in-space assembly and construction capability for large and/or massive spacecraft. The in-space assembly and construction technology program will support the need to build, in orbit, the full range of spacecraft required for the missions to and from planet Earth, including: earth-orbiting platforms, lunar transfer vehicles, and Mars transfer vehicles.

Bush, Harold↗
NASA NTRS1991

SPECS: Orbital debris removal

The debris problem has reached a stage at which the risk to satellites and spacecraft has become substantial in low Earth orbit (LEO). This research discovered that small particles posed little threat to spacecraft because shielding can effectively prevent these particles from damaging the spacecraft. The research also showed that, even though collision with a large piece of debris could destroy the spacecraft, the large pieces of debris pose little danger because they can be tracked and the spacecraft can be maneuvered away from these pieces. Additionally, there are many current designs to capture and remove large debris particles from the space environment. From this analysis, it was decided to concentrate on the removal of medium-sized orbital debris, that is, those pieces ranging from 1 cm to 50 cm in size. The current design incorporates a transfer vehicle and a netting vehicle to capture the medium-sized debris. The system is based near an operational space station located at 28.5 deg inclination and 400 km altitude. The system uses ground-based tracking to determine the location of a satellite breakup or debris cloud. These data are uploaded to the transfer vehicle, which proceeds to rendezvous with the debris at a lower altitude parking orbit. Next, the netting vehicle is deployed, tracks the targeted debris, and captures it. After expending the available nets, the netting vehicle returns to the transfer vehicle for a new netting module and continues to capture more debris in the target area. Once all the netting modules are expended, the transfer vehicle returns to the space station's orbit where it is resupplied with new netting modules from a space shuttle load. The new modules are launched by the shuttle from the ground and the expended modules are taken back to Earth for removal of the captured debris, refueling, and repacking of the nets. Once the netting modules are refurbished, they are taken back into orbit for reuse. In a typical mission, the system has the ability to capture 50 pieces of orbital debris. One mission will take approximately six months and the system is designed to allow for a 30 deg inclination change on the outgoing and incoming trips of the transfer vehicle.

Source record↗
NASA NTRS1981

Liquid Rocket Propulsion Technology: An evaluation of NASA's program

The liquid rocket propulsion technology needs to support anticipated future space vehicles were examined including any special action needs to be taken to assure that an industrial base in substained. Propulsion system requirements of Earth-to-orbit vehicles, orbital transfer vehicles, and planetary missions were evaluated. Areas of the fundamental technology program undertaking these needs discussed include: pumps and pump drives; combustion heat transfer; nozzle aerodynamics; low gravity cryogenic fluid management; and component and system life reliability, and maintenance. The primary conclusion is that continued development of the shuttle main engine system to achieve design performance and life should be the highest priority in the rocket engine program.

Source record↗
NASA NTRS1989

Progress toward an integrated advanced transportation system

Long term mission and payload mass requirements have been inventoried in NASA's Civil Needs Data Base, thereby establishing a framework for the analysis of launch vehicle requirements as well as time-frame requirements for the availability of specific launch vehicle and orbit-transfer vehicle capabilities. The Next Manned Transportation System studies conducted within this framework focus on the definition of options for manned flight operations beyond current Space Shuttle capabilities. Also under way are Assured Crew Return Capability studies for the Space Station Freedom, and Space Transfer Vehicle studies for a space-based aerobraking spacecraft.

Branscome, Darrell R.↗
NASA NTRS1986

Orbital spacecraft resupply technology

The resupplying of orbital spacecraft using the Space Shuttle, Orbital Maneuvering Vehicle, Orbital Transfer Vehicle or a depot supply at a Space Station is studied. The governing factor in fluid resupply designs is the system size with respect to fluid resupply quantities. Spacecraft propellant management for tankage via diaphragm or surface tension configurations is examined. The capabilities, operation, and application of adiabatic ullage compression, ullage exchange, vent/fill/repressurize, and drain/vent/no-vent fill/repressurize, which are proposed transfer methods for spacecraft utilizing tankage configurations, are described. Selection of the appropriate resupply method is dependent on the spacecraft design features. Hydrazine adiabatic compression/detonation, liquid-free vapor venting to prevent freezing, and a method for no-vent liquid filling are analyzed. Various procedures for accurate measurements of propellant mass in low gravity are evaluated; a system of flowmeters with a PVT system was selected as the pressurant solubility and quantity gaging technique. Monopropellant and bipropellant orbital spacecraft consumable resupply system tanks which resupply 3000 lb of hydrazine and 7000 lb of MMH/NTO to spacecraft on orbit are presented.

Eberhardt, R. N.↗
NASA NTRS1976

OAST Space Theme Workshop. Volume 3: Working group summary. 9: Aerothermodynamics (M-3). A: Statement. B: Technology needs (form 1). C. Priority assessment (form 2). D. Additional assessments

Twelve aerothermodynamic space technology needs were identified to reduce the design uncertainties in aerodynamic heating and forces experienced by heavy lift launch vehicles, orbit transfer vehicles, and advanced single stage to orbit vehicles for the space transportation system, and for probes, planetary surface landers, and sample return vehicles for solar system exploration vehicles. Research and technology needs identified include: (1) increasing the fluid dynamics capability by at least two orders of magnitude by developing an advanced computer processor for the solution of fluid dynamic problems with improved software; (2) predicting multi-engine base flow fields for launch vehicles; and (3) developing methods to conserve energy in aerothermodynamic ground test facilities.

Source record↗
NASA NTRS1981

Safety aspects of nuclear waste disposal in space

Safety issues involved in the disposal of nuclear wastes in space as a complement to mined geologic repositories are examined as part of an assessment of the feasibility of nuclear waste disposal in space. General safety guidelines for space disposal developed in the areas of radiation exposure and shielding, containment, accident environments, criticality, post-accident recovery, monitoring systems and isolation are presented for a nuclear waste disposal in space mission employing conventional space technology such as the Space Shuttle. The current reference concept under consideration by NASA and DOE is then examined in detail, with attention given to the waste source and mix, the waste form, waste processing and payload fabrication, shipping casks and ground transport vehicles, launch site operations and facilities, Shuttle-derived launch vehicle, orbit transfer vehicle, orbital operations and space destination, and the system safety aspects of the concept are discussed for each component. It is pointed out that future work remains in the development of an improved basis for the safety guidelines and the determination of the possible benefits and costs of the space disposal option for nuclear wastes.

Rice, E. E.↗