SEARCH · Search NASA

Results for “STORABLE PROPELLANT”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10

All sources NASA NTRS DOE OSTI

NASA NTRS1980

Chemical vapor deposited tungsten with dispersed carbides for Space Shuttle check valves

A chemical vapor deposited tungsten with dispersed carbides was selected as the material for Space Shuttle Orbital Maneuvering and Reaction Control Systems check valve poppets and seats. The selection followed a NASA-sponsored prototype check valve development program utilizing the cutter-seal shell poppet concept. The poppet material is deposited as a coating approximately 0.9 mm thick and fabricated into a shell as a free standing body. The seat material is deposited as a coating 1.1 mm thick on a seat blank, and the cutter seal is machined in the coating. Module tests demonstrated that the material could be ground and lapped to very sharp edges and could cut through typical system contaminants without excessive damage to the sealing surfaces. The material was also determined to be unaffected by exposure to a strongly oxidizing storable propellant.

Williams, G. E.↗

NASA NTRS1974

Space Tug systems study (storable). Volume 1: Overview presentation

Program plans are established for a storable propellant space tug used to perform high energy orbit transfers from the space transportation system (STS) orbiter. The mission model for the STS in the 1980's is analyzed. Performance and mission requirements are determined. Various flight operations modes are evaluated and selected. Subsystems are selected and synthesized into various tug configurations. Program options for these configurations are defined, analyzed, and selected. Selected program options are further defined and optimized, including program requirements, tug vehicle definition, mission accomplishment, ground and flight operations, programmatics and costs.

Source record↗

NASA NTRS1974

Space Tug systems study. Volume 2: Compendium

Possible storable propellant configurations and program plans are evaluated for the space tug. Alternatives examined include: use of existing expendable stages modified for use with shuttle, followed by a space tug at a later date; use of a modified growth version of existing expendable stages for greater performance and potential reuse, followed by a space tug at a later date; use of a low development cost, reusable, interim space tug available at shuttle initial operational capability (IOC) that could be evolved to greater system capabilities at a later date; and use a direct developed tug with maximum potential to be available at some specified time after space shuttle IOC. The capability options were narrowed down to three final options for detailed program definition.

Source record↗

NASA NTRS1982

Storable orbit transfer vehicle

Orbit transfer vehicles (OTV) are evaluated against mission model requirement. Mission suitability of OTVs using storable propellant, cryogenic propellant, and electric propulsion systems is outlined. Energy required, g-level, spacecraft deploy/return, operational constraints, mission duration, and packaging are considered.

Pipes, W. E.↗

NASA NTRS1982

Propulsion system options for low-acceleration orbit transfer

The present inventory of developed bipropellant engines suitable for the orbit transfer of large space structures is based on the use of storable propellants (nitrogen tetroxide/monomethyl hydrazine). A range of engine sizes from 22N (5 lbF) to over 26,690N (6000 lbF) is available. These engines are capable of delivering specific impulse values from 2795 to 3089 N-s/kg (285 to 315 lbF-sec/lbm). A comparison is made between the attainable specific impulse of these demonstrated engines and future low-thrust engine designs which can utilize LOX/RP-1, LOX-methane, and LOX/hydrogen propellants. The requirements for cooling these small engines for multi-hour burns as well as the merits of operating at nonoptimum performance mixture ratios to improve cooling margins and reduce tank volumes are addressed in this paper.

Schoenman, L.↗

NASA NTRS1982

Propellant/material compatibility program and results: Ten-year milestones

The analyses and results of a test program to establish the effects of long term (10 years or more) contact of materials with earth-storable propellants for the purpose of designing chemical propulsion system components which are used for current as well as future planetary spacecraft are described. The period from the publication of JPL TM 33-779 IN 1976 through the testing accomplished in 1981 is covered. The following propellants are reported herein: hydrazine, monomethylhydrazine and nitrogen tetroxide. Materials included the following: aluminum alloys, corrosion resistant steels and a titanium alloy. The results of the testing of more than 80 specimens are included. Material ratings relative to the ten year milepost were assigned. Some evidence of propellant decomposition was found. Titanium is rated as acceptable for ten year applications. Aluminum and stainless steel alloys are also rated as acceptable with few restrictions.

Moran, C.↗

NASA NTRS1986

NASA electrothermal auxiliary propulsion technology

Electrothermal auxiliary propulsion systems provide high performance options which can have major mission benefits. There are several electrothermal concepts which offer a range of characteristics and benefits. Resistojets are the highest thrust to power option and are currently operational at mission average values of specific impulse, I sub sp approximately 295 sec. Long life, multipropellant resistojets are being developed for the space station, and resistojet technology advancements are being pursued to improve the I sub sp by more than 20 percent for resistojets used in satellite applications. Direct current arcjets have the potential of I sub sp over 400 sec with storable propellants and should provide over 1000 sec with hydrogen. Advanced concepts are being investigated to provide high power density options and possible growth to primary propulsion applications. Broad based experimental and analytical research and technology programs of NASA are summarized and recent significant advances are reviewed.

Stone, J. R.↗

NASA NTRS1985

Beyond low earth orbit - An overview of orbit-to-orbit stages

New developments in upper stages are discussed. Tables revealing the dimensions, engine types, total thrust, weight, payload, and sponsor for developed and planned upper stages compatible with Space Transportation System (STS) or expendable launch vehicles are presented. An example of STS delivery capability to the Space Station at various orbital altitudes is provided. The use of aerobraking as the propulsion strategy for reusable stages is investigated. Various methods of controlling spent stages and maintaining a fragment free space environment are described. Storable propellant transfer systems and handling techniques for cryogens are studied.

Loftus, J. P., Jr.↗

NASA NTRS1986

Uprated OMS engine status and future applications

The baseline Orbital Maneuvering Engine (OME) of the Space Shuttle has the potential for significant performance uprating, leading to increased Shuttle performance capability. The approach to uprating that is being pursued at the NASA Lyndon B. Johnson Space Center is the use of a gas generator-driven turbopump to increase OME operating pressure. A higher pressure engine can have a greater nozzle expansion ratio in the same envelope and at the same thrust level, giving increased engine Isp. The results of trade studies and analyses that have led to the preferred uprated OME configuration are described. The significant accomplishments of a pre-development component demonstration program are also presented, including descriptions of test hardware and discussion of test results. It is shown that testing to date confirms the capability of the preferred uprated OME configuration to meet or exceed performance and life requirements. Potential future activities leading up to a full-scale development program are described, and the capability for the uprated OME to be used in future storable propellant upper stages is discussed.

Boyd, W. C.↗

NASA NTRS1986

NASA electrothermal auxiliary propulsion technology

Electrothermal auxiliary propulsion systems provide high performance options which can have major mission benefits. There are several electrothermal concepts which offer a range of characteristics and benefits. Resistojets are the highest thrust to power option and are currently operational at mission average values of specific impulse, I sub sp approximately 295 sec. Long life, multipropellant resistojets are being developed for the Space Station, and resistojet technology advancements are being pursued to improve the I sub sp by more than 20 percent for resistojets used in satellite applications. Direct current arcjets have the potential of I sub sp over 400 sec with storable propellants and should provide over 1000 sec with hydrogen. Advanced concepts are being investigated to provide high power density options and possible growth to primary propulsion applications. Broad based experimental and analytical research and technology programs of NASA are summarized and recent significant advances are reviewed.

Stone, J. R.↗

NASA NTRS1987

The NASA/USAF arcjet research and technology program

Direct current arcjets have the potential to provide specific impulses greater than 500 sec with storable propellants, and greater than 1000 sec with hydrogen. This level of performance can provide significant benefits for such applications as orbit transfer, station keeping, orbit change, and maneuvering. The simplicity of the arcjet system and its elements of commonality with state-of-the-art resistojet systems offer a relatively low risk transition to these enhanced levels of performance for low power (0.5 to 1.5 kW) station keeping applications. Arcjets at power levels of 10 to 30 kW are potentially applicable to orbit transfer missions. Furthermore, with the anticipated development of space nuclear power systems, arcjets at greater than 100 kW may become attractive. This paper describes the ongoing NASA/USAF program and describes major recent accomplishments.

Stone, James R.↗

NASA NTRS1987

An analysis of bipropellant neutralization for spacecraft refueling operations

Refueling of satellites on orbit with storable propellants will involve venting part or all of the pressurant gas from the propellant tanks. This gas will be saturated with propellant vapor, and it may also have significant amounts of entrained fine droplets of propellant. The two most commonly used bipropellants, monomethyl hydrazine (MMH) and nitrogen tetroxide (N2O4), are highly reactive and toxic. Various possible ways of neutralizing the vented propellants are examined. The amount of propellant vented in a typical refueling operation is shown to be in the range of 0.2 to 5% of the tank capacity. Four potential neutralization schemes are examined: chemical decomposition, chemical reaction, condensation and adsorption. Chemical decomposition to essentially inert materials is thermodynamically feasible for both MMH and N2O4. It would be the simplest and easiest neutralization method to implement. Chemical decomposition would require more complex control. Condensation would require a refrigeration system and a very efficent phase separator. Adsorption is likely to be much heavier. A preliminary assessment of the four neutralization shemes is presented, along with suggested research and development plans.

Kauffman, David↗

NASA NTRS1985

System technology analysis of aeroassisted orbital transfer vehicles. Moderate lift/drag (0.75-1.5): Volume 1A, part 2: Executive summary, phase 2

Significant achievements and activities of Phase 2 of a study to assess aeroassisted orbit transfer vehicle (AOTV) system technology are summarized. Phase 2 was directed towards identification and prioritization of technology payoffs of representative space based mid lift/drag ratio (L/D) AOTV's and the cryofueled propulsion subsystem - configuration interactions. Enhancing technology areas were identified which could provide substantial transport cost reduction. These include: (1) improved lifetime of storable propellant engines; (2) avionics weight reduction; (3) external thermal protection system weight reduction; (4) decrease of uncertainties in aerodynamic and aerothermodynamic performance; electrical power subsystem weight reduction due to incorporation of advanced materials; and (6) structural shell weight reduction. Results indicated that advanced aerothermodynamic methodology and aft end configuring may provide an enlarged allowable zone for engine nozzle protrusions into the separated flow region. Payload manifesting and non-hydrogen propellant manifesting at the space station is recommended.

Source record↗

NASA NTRS1986

Uprated OMS engine for upper stage propulsion

The results of a pre-development component demonstration program on the use of a gas generator-driven turbopump that increases the Space Shuttle's Orbital Maneuvering Engine (OME) operating pressure are given. Tests and analysis confirm the the capability of the concept to meet or exceed performance and life requirements. Storable propellant upper stage concepts are also discussed.

Boyd, William C.↗

NASA NTRS1987

The NASA/USAF arcjet research and technology program

Stone, James R.↗

NASA NTRS1987

Orbital Spacecraft Consumables Resupply System (OSCRS). Volume 2: Study results

The objective was to establish an earth storable fluids tanker concept which satisfies the initial resupply requirements for the Gamma Ray Observatory (GRO) for reasonable front end (design, development, verification) cost while providing growth potential for foreseeable future earth storable resupply mission requirements. The achievement of these objectives becomes possible with the development of a modularized tanker concept which is a hybrid of a dedicated GRO tanker and a generic earth storable propellant tanker.

Source record↗

NASA NTRS1988

Operational cost drivers

To be economically viable, the operations cost of launch vehicles must be reduced by an order of magnitude as compared to the Space Transportation System (STS). A summary of propulsion-related operations cost drivers derived from a two-year study of Shuttle ground operations is presented. Examples are given of the inordinate time and cost of launch operations caused by propulsion systems designs that did not adequately consider impacts on prelaunching processing. Typical of these cost drivers are those caused by central hydraulic systems, storable propellants, gimballed engines, multiple propellants, He and N2 systems and purges, hard starts, high maintenance turbopumps, accessibility problems, and most significantly, the use of multiple, nonintegrated RCS, OMS, and main propulsion systems. Recovery and refurbishment of SRBs have resulted in expensive crash and salvage operations. Vehicle system designers are encouraged to be acutely aware of these cost drivers and to incorporate solutions (beginning with the design concepts) to avoid business as usual and costs as usual.

Scholz, Arthur L.↗

NASA NTRS1990

Space Shuttle vernier thruster long-life chamber development

The Space Shuttle Reaction Control Subsystem (RCS) vernier thruster is a pressure fed engine that utilizes storable propellants to provide precise attitude control for the Orbiter. The current vernier thruster is life limited due to its chamber material. By developing an iridium-lined rhenium chamber for the vernier, substantial gains could be achieved in the operational life of the chamber. The present RCS vernier, its requirements, operating characteristics, and life limitations are described. The current technology status of iridium-lined rhenium is presented along with a description of the operational life capabilities to be gained from implementing this material into the design of a long life vernier chamber. Discussion of the proposed demonstration program to be performed by the NASA Lyndon B. Johnson Space Center to attain additional insight into the application of this technology to the RCS vernier, includes the technical objectives, approach, and program schedule. The plans for further development and integration with the Orbiter and the Shuttle system are also presented.

Krohn, Douglas D.↗