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START-3: Operational Evaluations of the ISUS Engine Ground Demonstration Thermionic Power System

Description: START-3 was a test program conducted in order to demonstrate and characterize the operational performance of the prototype Integrated Solar Upper Stage (ISUS) thermionic power system. The test device consisted of a graphite thermal storage uni~ multilayer foil insulation, and sixteen thermionic converters electrically connected in a series array. Several thermal input conditions were achieved during the test, which resulted in measuring converter performance at average converter hot shoe temperatures in the range of 1600 K to 2000 K. Results indicate that the ;hermionic converter; did not perform as weil as expected in the array individual sixteen converters is currently being performed.
Date: October 8, 1998
Creator: Luchau, D.W.; Luke, J.R. & Wyant, F.J.
Partner: UNT Libraries Government Documents Department

Performance test plan for a space station toluene heater tube

Description: Sundstrand Energy Systems was awarded a contract to investigate the performance capabilities of a toluene heater tube integral to a heat pipe as applied to the Organic Rankine Cycle (ORC) solar dynamic power system for the Space Station. This heat pipe is a subassembly of the heat receiver. The heat receiver, the heat absorption component of the ORC solar dynamic power system, consists of forty liquid metal heat pipes located circumferentially around the heat receiver`s outside diameter. Each heat pipe contains a toluene heater, two thermal energy storage (TES) canisters and potassium. The function of the heater tube is to heat the supercritical toluene to the required turbine inlet temperature. During the orbit of the space station, the heat receiver and thereby the heat pipe and heater tube will be subjected to variable heat input. The design of the heater must be such that it can accommodate the thermal and hydraulic variations that will be imposed upon it.
Date: October 1, 1987
Creator: Parekh, M.B.
Partner: UNT Libraries Government Documents Department

Space tug applications. Final report

Description: This article is the final report of the conceptual design efforts for a `space tug`. It includes preliminary efforts, mission analysis, configuration analysis, impact analysis, and conclusions. Of the several concepts evaluated, the nuclear bimodal tug was one of the top candidates, with the two options being the NEBA-1 and NEBA-3 systems. Several potential tug benefits were identified during the mission analysis. The tug enables delivery of large (>3,500 kg) payloads to the outer planets and it increases the GSO delivery capability by 20% relative to current systems. By providing end of life disposal, the tug can be used to extend the life of existing space assets. It can also be used to reboost satellites which were not delivered to their final orbit by the launch system. A specific mission model is the key to validating the tug concept. Once a mission model can be established, mission analysis can be used to determine more precise propellant quantities and burn times. In addition, the specific payloads can be evaluated for mass and volume capability with the launch systems. Results of the economic analysis will be dependent on the total years of operations and the number of missions in the mission model. The mission applications evaluated during this phase drove the need for large propellant quantities and thus did not allow the payloads to step down to smaller and less expensive launch systems.
Date: January 1, 1996
Partner: UNT Libraries Government Documents Department

Quantifying the heat switching capability of a thermionic diode

Description: The Integrated Solar Upper Stage (ISUS) Advanced Technology Demonstrator (ATD) program, recently initiated by the US Air Force Phillips Laboratory (USAF PL), will demonstrate the feasibility of a combined solar power and propulsion upper stage. The solar bimodal design approach will use thermal energy storage to reduce engine mass and concentrator area. However, in order to store enough energy over an orbit period there must be minimal heat lost with a system that is designed to remove heat for energy conversion. A unique feature of thermionics is their ability to reduce heat flow by reducing or eliminating the electron cooling. However, demonstration and quantification of this capability is needed. This paper presents the results to date of the Receiver Diode Integration Test, one of two critical experiments of the ISUS ATD program being performed by the Idaho National Engineering Laboratory (INEL). Results of the demonstration testing of thermionic heat pipe modules (THPMs) to operate as heat switches in conjunction with the solar receiver cavity are presented as are the performance limits and operational constraints of a combined receiver/diode subsystem.
Date: December 1, 1995
Creator: Snyder, A. M. & Verrill, D. A.
Partner: UNT Libraries Government Documents Department

Solar dynamic heat pipe development and endurance test. Monthly technical progress report number 3, 28 July--27 August 1987

Description: The Space Station requires a high-level of reliable electric power. The baseline approach is to utilize a hybrid system in which power is provided by photovoltaic arrays and by solar dynamic power conversion modules. The organic Rankine cycle (ORC) engine is one approach to solar dynamic conversion. The ORC provides the attributes of high efficiency at low temperature and compact simple designs utilizing conventional techniques and materials. The heat receiver is one area which must be addressed in applying the proven ORC to long life applications such as the Space Station. Heat pipes with integral thermal energy storage (TES) canisters and a toluene heater tube are the prime components of the heat receiver from the Phase B preliminary design. This contract is a task order type addressing the design, fabrication and testing of a full scale heat pipe. The primary activities during the report period were the fabrication of three 74.4 inch long LiOH canisters and a 72 inch long toluene heater tube. Progress on other tasks and objectives of future tasks are described.
Date: September 3, 1987
Creator: Parekh, M.B.
Partner: UNT Libraries Government Documents Department

Multidimensional simulation studies of the SELENE FEL oscillator/buncher followed by a radiator/amplifier output scheme

Description: We analyze and present numerical simulations of the so-called electron output scheme [G. I. Erg et al., 15th Int. FEL Conf., The Hague, The Netherlands, 1993, Book of Abstracts p. 50; Preprint Budker INP 93-75] applied to the SELENE proposal of using a high power FEL to illuminate satellite solar cells. In this scheme, a first stage FEL oscillator bunches the electron beam while a second stage ``radiator`` extracts high power radiation. Our analysis suggests only in the case where the radiator employs a long, tapered undulator will the electron output scheme produce a significant increase in extraction efficiency over what is obtainable from a simple, single-stage oscillator. 1- and 2-D numerical simulations of a 1.7{mu}m FEL employing the electron output scheme show reasonably large bunching fractions ({approximately} 0.3--0.4) at the output of the oscillator stage but only {le}2% extraction efficiency from the radiator stage.
Date: February 1, 1995
Creator: Hahn, S.J. & Fawley, W.M.
Partner: UNT Libraries Government Documents Department

Solar dynamic heat pipe development and endurance test. Monthly technical progress report number 5, 30 September--28 October, 1987

Description: The Space Station requires a high level of reliable electric power. The baseline approach is to utilize a hybrid system in which power is provided by photovoltaic arrays and by solar dynamic power conversion modules. The organic Rankine cycle (ORC) engine is one approach to solar dynamic conversion. The ORC provides the attributes of high efficiency at low temperature and compact simple designs utilizing conventional techniques and materials. The heat receiver is one area which must be addressed in applying the proven ORC to long life applications such as the Space Station. Heat pipes with integral thermal energy storage (TES) canisters and a toluene heater tube are the prime components of the heat receiver from the Phase B preliminary design. This contract is a task order type addressing the design, fabrication and testing of a full scale heat pipe. The contract was initiated on April 16, 1987. Sundstrand has specific responsibilities in each task. Los Alamos National Laboratory (LANL) in turn has the prime contract responsibility to NASA-LeRC.
Date: October 28, 1987
Creator: Parekh, M.B.
Partner: UNT Libraries Government Documents Department

Solar dynamic heat pipe development and endurance test. Monthly technical progress report number 6, 29 October--November 30, 1987

Description: The Space Station requires a high level of reliable electric power. The baseline approach is to utilize a hybrid system in which power is provided by photovoltaic arrays and by solar dynamic power conversion modules. The organic Rankine cycle (ORC) engine is one approach to solar dynamic conversion. The ORO provides the attributes of high efficiency at low temperature and compact simple designs utilizing conventional techniques and materials. The heat receiver is one area which must be addressed in applying the proven ORC to long life applications such as the Space Station. Heat pipes with integral thermal energy storage (TES) canisters and a toluene heater tube are the prime components of the heat receiver from the Phase B preliminary design. This contract is a task order type addressing the design, fabrication and testing of a full scale heat pipe. The contract was initiated on April 16, 1987. Sundstrand has specific responsibilities in each task. Los Alamos National Laboratory (LANL) in turn has the prime contract responsibility to NASA-LeRC.
Date: December 7, 1987
Creator: Parekh, M.B.
Partner: UNT Libraries Government Documents Department

Cycle life testing of lithium-ion batteries for small satellite LEO space missions

Description: In 1990, Sony corporation announced their intention to manufacture a rechargeable lithium ion battery, based on the intercalation of lithium ions into a carbonaceous anode. The cells were first introduced for portable telephone use in June, 1991. (1) A 3.6V average cell voltage (4.1-2.75V range); (2) Excellent cycle life (1200 @ 100% DOD); (3) Good capacity retention (70% after 6 months); (4) Wide temperature range performance ({minus}20 to +60{degrees}C); (5) Excellent Discharge rate (82% capacity at 30 min. discharge rate); (6) Excellent Charge rate (100% Charge in <3 hrs); and (7) High energy density (264 W*hr/1 and 120 Whr/kg for ``D`` size cell. These specifications show significant promise for application of these batteries in low earth orbit (LEO) small satellites, particularly when compared to existing NiH{sub 2} and NiCd technology. The very high energy density and specific energy will reduce power system volume and weight. The wide temperature range enables simpler thermal design, particularly for new, small, high power satellites. The materials used in the lithium ion batteries are relatively inexpensive and benign, so that we expect costs to come down substantially in the future. The specified cycle life at 100% DOD is also 50% longer than most NiCds, so low DOD (depth of discharge) performance could be substantial. This study was undertaken to: (a) assess the feasibility for using lithium ion cells on small satellite LEO missions and (b) verify the claims of the manufacturer. This was accomplished by performing a detailed autopsy and various depth of discharge and rate tests on the cells. Of special interest was the cycle life performance of these cell at various depths of discharge DOD`s, to get an initial measure of the reduction in capacity fade with cycle conditions. Low DOD`s are used to extend the life of all batteries used in a …
Date: August 16, 1993
Creator: Mayer, S. T.; Feikert, J. H. & Kaschmitter, J. L.
Partner: UNT Libraries Government Documents Department

Water rocket - Electrolysis propulsion and fuel cell power

Description: Water Rocket is the collective name for an integrated set of technologies that offer new options for spacecraft propulsion, power, energy storage, and structure. Low pressure water stored on the spacecraft is electrolyzed to generate, separate, and pressurize gaseous hydrogen and oxygen. These gases, stored in lightweight pressure tanks, can be burned to generate thrust or recombined to produce electric power. As a rocket propulsion system, Water Rocket provides the highest feasible chemical specific impulse (-400 seconds). Even higher specific impulse propulsion can be achieved by combining Water Rocket with other advanced propulsion technologies, such as arcjet or electric thrusters. With innovative pressure tank technology, Water Rocket's specific energy [Wh/kg] can exceed that of the best foreseeable batteries by an order of magnitude, and the tanks can often serve as vehicle structural elements. For pulsed power applications, Water Rocket propellants can be used to drive very high power density generators, such as MHD devices or detonation-driven pulse generators. A space vehicle using Water Rocket propulsion can be totally inert and non-hazardous during assembly and launch. These features are particularly important for the timely development and flight qualification of new classes of spacecraft, such as microsats, nanosats, and refuelable spacecraft.
Date: July 24, 1999
Creator: Carter, P. H.; Dittman, M. D.; Kare, J. T.; Militsky, F.; Myers, B. & Weisberg, A. H.
Partner: UNT Libraries Government Documents Department

FEL options for power beaming

Description: The demand for the output power of communication satellites has been increasing exponentially. The satellite power is generated from solar panels which collect the sunlight and convert it to electrical power. The power per satellite is limited due to the limit in the practical size of the solar panel. One way to meet the power demand is to employ multiple satellites (up to 10) per the internationally agreed-upon ``slot`` in the geosynchronous earth orbit (GEO). However, this approach is very expensive due to the high cost of sending a satellite into a GEO orbit. An alternative approach is power beaming, i.e., to illuminate the solar panels with high power, highly-directed laser beams from earth. The power beaming generates more power per satellite for the same area of the solar panel. The minimum optical beam power, interesting for power beaming application, is P{sub L} = 200kW. The wavelength is chosen to be {lambda} = 0.84 {micro}m, so that it is within one of the transmission windows of the air, and at the same time near the peak of the photo-voltaic conversion efficiency of Si, which is the commonly used material for the solar panels. Free electron lasers (FELs) are well suited for the power beaming application because they can provide high power with coherent wavefront, but without high energy density in media. In this article the authors discuss some principal issues, such as the choice of accelerator and electron gun, the choice of beam parameters, radiation hazards, technological availability, and overall efficiency and reliability of the installation. They also attempt to highlight the compromise between the cost of the primary installation, the operation cost, and the choice of technology, and its maturity. They then present several schemes for the accelerator-FEL systems based on RF accelerators. The initial electron beam accelerator up …
Date: October 1, 1997
Creator: Kim, K. J.; Zholents, A. A.; Zolotorev, M. S. & Vinokurov, N. A.
Partner: UNT Libraries Government Documents Department

A compendium of the radioisotope thermoelectric generator transportation system and recent programmatic changes

Description: Because RTGs contain significant quantities of radioactive materials, usually plutonium-238 and its decay products, they must be transported in packages built in accordance with 10 CFR 71 (1994). To meet these regulatory requirements, US DOE commissioned Westinghouse Hanford Co. in 1988 to develop a Radioisotope Thermoelectric Generator Transportation System (RTGTS) that would fully comply while protecting RTGs from adverse environmental conditions during normal transport conditions (eg, mainly shock and heat). RTGTS is scheduled for completion Dec. 1996 and will be available to support NASA`s Cassini mission to Saturn in Oct. 1997. This paper provides an overview of the RTGTS project, discusses the hardware being produced, and summarizes various programmatic and management innovations required by recent changes at DOE.
Date: March 1, 1996
Creator: Becker, D. L. & McCoy, J. C.
Partner: UNT Libraries Government Documents Department

ANNUAL TECHNICAL PROGRESS REPORT OF RADIOISOTOPE POWER SYSTEMS MATERIALS PRODUCTION AND TECHNOLOGY PROGRAM TASKS FOR OCTOBER 1, 2010 THROUGH SEPTEMBER 30, 2011

Description: The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration (NASA) for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, the Oak Ridge National Laboratory (ORNL) produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. These components were also produced for the Pluto New Horizons and Mars Science Lab missions launched in January 2006 and November 2011respectively. The ORNL has been involved in developing materials and technology and producing components for the DOE for nearly four decades. This report reflects program guidance from the Office of RPS for fiscal year (FY) 2011. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new RPS. Work has also been initiated to establish fabrication capabilities for the Light Weight Radioisotope Heater Units.
Date: May 1, 2012
Creator: King, James F.
Partner: UNT Libraries Government Documents Department

New vision solar system exploration missions study: Analysis of the use of biomodal space nuclear power systems to support outer solar system exploration missions. Final report

Description: This report presents the results of an analysis of the capability of nuclear bimodal systems to perform outer solar system exploration missions. Missions of interest include orbiter mission s to Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial technology baseline consisting of a NEBA 10 kWe, 1000 N thrust, 850 s, 1500 kg bimodal system was selected, and its performance examined against a data base for trajectories to outer solar system planetary destinations to select optimal direct and gravity assisted trajectories for study. A conceptual design for a common bimodal spacecraft capable of performing missions to all the planetary destinations was developed and made the basis of end to end mission designs for orbiter missions to Jupiter, Saturn, and Neptune. Concepts for microspacecraft capable of probing Jupiter`s atmosphere and exploring Titan were also developed. All mission designs considered use the Atlas 2AS for launch. It is shown that the bimodal nuclear power and propulsion system offers many attractive option for planetary missions, including both conventional planetary missions in which all instruments are carried by a single primary orbiting spacecraft, and unconventional missions in which the primary spacecraft acts as a carrier, relay, and mother ship for a fleet of micro spacecraft deployed at the planetary destination.
Date: December 8, 1995
Partner: UNT Libraries Government Documents Department

Heatpipe power system development

Description: This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of the project was to develop a design approach that could enable the development of near-term, low-cost, space fission-power systems. Sixteen desired attributes were identified for such systems and detailed analyses were performed to verify that they are feasible. Preliminary design work was performed on one concept, the Heatpipe Power system (HPS). As a direct result of this project, funding was obtained from the National Aeronautics and Space Administration to build and test an HPS module. The module tests went well, and they now have funding to build a bimodal module.
Date: December 31, 1998
Creator: Houts, M. G. & Poston, D. I.
Partner: UNT Libraries Government Documents Department

GPHS-RTGs in support of the Cassini Mission. Semi-annual technical progress report, April 3, 1995--October 1, 1995

Description: This document is the April-October 1995 Progress Report on the Cassini RTG Program. Nine tasks are summarized; (1) Spacecraft integration and liason, (2) Engineering support, (3) Safety, (4) Unicouple fabrication, (5) ETG fabrication, assembly, and test, (6) Ground support equipment, (7) RTG shipping and launch support, (8) Design, reviews, and mission applications, and (9) Project management, QA, contract changes, and material acquisitions.
Date: October 24, 1995
Partner: UNT Libraries Government Documents Department

Radioisotope electric propulsion of sciencecraft to the outer solar system and near-interstellar space

Description: Recent results are presented in the study of radioisotope electric propulsion as a near-term technology for sending small robotic sciencecraft to the outer Solar System and near-interstellar space. Radioisotope electric propulsion (REP) systems are low-thrust, ion propulsion units based on radioisotope electric generators and ion thrusters. Powerplant specific masses are expected to be in the range of 100 to 200 kg/kW of thrust power. Planetary rendezvous missions to Pluto, fast missions to the heliopause (100 AU) with the capability to decelerate an orbiter for an extended science program and prestellar missions to the first gravitational lens focus of the Sun (550 AU) are investigated.
Date: August 1, 1998
Creator: Noble, R.J.
Partner: UNT Libraries Government Documents Department

Lightweight transformer demonstration. Quarterly status report, 27 March 1989--25 June 1989

Description: Information is presented on progress made during the reporting period: 3/27/89--6/25/89. The project goal is to support highly focused, innovative, fundamental/applied research approaches that will complement the Feasibility Assessment Program for Space Based, Multimegawatt, MHD Power Systems.(JDB)
Date: December 31, 1989
Partner: UNT Libraries Government Documents Department

Lightweight transformer demonstration. Semiannual status report, 1 April 1988--30 September 1988

Description: Information is presented on progress made during the reporting period: 4/1/88--9/30/88. The project goal is to support highly focused, innovative, fundamental/applied research approaches that will complement the Feasibility Assessment Program for Space Based, Multimegawatt, MHD Power Systems.(JDB)
Date: December 31, 1988
Partner: UNT Libraries Government Documents Department

Lightweight transformer demonstration. Semiannual status report, 1 October 1987--31 March 1988

Description: Information is presented on progress made during the reporting period: 10/1/87--3/31/88. The project goal is to support highly focused, innovative, fundamental/applied research approaches that will complement the Feasibility Assessment Program for Space Based, Multimegawatt, MHD Power Systems. (JDB)
Date: December 31, 1988
Partner: UNT Libraries Government Documents Department
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