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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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Advanced Dependent Pressure Vessel (DPV) nickel-hydrogen spacecraft cell and battery design

The dependent pressure vessel (DPV) nickel-hydrogen (NiH2) battery is being developed as a potential spacecraft battery design for both military and commercial satellites. Individual pressure vessel (IPV) NiH2 batteries are currently flying on more than 70 Earth orbital satellites and have accumulated more than 140,000,000 cell-hours in actual spacecraft operation. The limitations of standard NiH2 IPV flight battery technology are primarily related to the internal cell design and the battery packaging issues associated with grouping multiple cylindrical cells. The DPV cell design offers higher specific energy and reduced cost, while retaining the established IPV NiH2 technology flight heritage and database. The advanced cell design offers a more efficient mechanical, electrical and thermal cell configuration and a reduced parts count. The internal electrode stack is a prismatic flat-plate arrangement. The flat individual cell pressure vessel provides a maximum direct thermal path for removing heat from the electrode stack. The cell geometry also minimizes multiple-cell battery packaging constraints by using an established end-plateltie-rod battery design. A major design advantage is that the battery support structure is efficiently required to restrain only the force applied to a portion of the end cell. As the cells are stacked in series to achieve the desired system voltage, this increment of the total battery weight becomes small. The geometry of the DPV cell promotes compact, minimum volume packaging and places all cell terminals along the length of the battery. The resulting ability to minimize intercell wiring offers additional design simplicity and significant weight savings. The DPV battery design offers significant cost and weight savings advantages while providing minimal design risks. Cell and battery level design issues will be addressed including mechanical, electrical and thermal design aspects. A design performance analysis will be presented at both the cell and battery level. The DPV is capable of delivering up to 76 Watt-hours per kilogram (Wh/kg) at the cell level and 70 Wh/kg at the full battery level. This represents a 40 percent increase in specific energy at the cell level and a 60 percent increase in specific energy at the battery level compared to current IPV NiH2 technology.

Coates, Dwaine↗

New Developments in Nickel-Hydrogen Dependent Pressure Vessel (DPV) Cell and Battery Design

THe Dependent Pressure Vessel (DPV) Nickel-Hydrogen (NiH2) design is being developed as an advanced battery for military and commercial, aerospace and terrestrial applications. The DPV cell design offers high specific energy and energy density as well as reduced cost, while retaining the established Individual Pressure Vessel (IPV) technology flight heritage and database. This advanced DPV design also offers a more efficient mechanical, electrical and thermal cell and battery configuration and a reduced part count. The DPV battery design promotes compact, minimum volume packaging and weight efficiency, and delivers cost and weight savings with minimal design risk.

Caldwell, Dwight B.↗

Advanced Dependent Pressure Vessel (DPV) Nickel-Hydrogen Spacecraft Cell and Battery Design

The dependent pressure vessel (DPV) nickel-hydrogen (Ni-H2) battery is being developed as a potential spacecraft battery design for both military and commercial satellites. Individual pressure vessel (IPV) Ni-H2 batteries are currently flying on more than 70 Earth-orbiting satellites and have accumulated more that 140,000,000 cell-hours in actual spacecraft operation. The limitations of standard Ni-H2 IPV flight battery technology are primarily related to the internal cell design and the battery packaging issues associated with grouping multiple cylindrical cells. The DPV cell design offers higher specific energy and reduced cost, while retaining the established IPV Ni-H2 technology flight heritage and database. A design performance analysis is presented at both the cell and battery level. The DPV is capable of delivering up to 76 Watthours per kilogram (Wh/kg) at the cell level and 70 Wh/kg at the full battery level. This represents a 40 percent increase in specific energy at the cell level and a 60 percent increase in specific energy at the battery level compared to current IPV Ni-H2 technology.

Dwaine K Coates↗

Data Presentation and Visualization (DPV) Interface Control Document

Data Presentation and Visualization (DPV) is a subset of the modeling and simulation (M&S) capabilities at Kennedy Space Center (KSC) that endeavors to address the challenges of how to present and share simulation output for analysts, stakeholders, decision makers, and other interested parties. DPV activities focus on the development and provision of visualization tools to meet the objectives identified above, as well as providing supporting tools and capabilities required to make its visualization products available and accessible across NASA.

Ontology↗

Asteroseismology of the DOV star PG 1159 - 035 with the Whole Earth Telescope

Results are reported from 264.1 hr of nearly continuous time-series photometry on the pulsating prewhite dwarf star (DPV) PG 1159 - 035. The power spectrum of the data set is completely resolved into 125 individual frequencies; 101 of them are identified with specific quantized pulsation modes, and the rest are completely consistent with such modal assignment. It is argued that the luminosity variations are certainly the result of g-mode pulsations. Although the amplitudes of some of the peaks exhibit significant variations on the time scales of a year or so, the underlying frequency structure of the pulsations is stable over much longer intervals. The existing linear theory is invoked to determine, or strongly constrain, many of the fundamental physical parameters describing this star. Its mass is found to be 0.586 solar mass, is rotation period 1.38 days, its magnetic field less than 6000 G, its pulsation and rotation axes to be aligned, and its outer layers to be compositionally stratified.

Winget, D. E.↗

Advanced nickel-hydrogen spacecraft battery development

Eagle-Picher currently has several advanced nickel-hydrogen (NiH2) cell component and battery designs under development including common pressure vessel (CPV), single pressure vessel (SPV), and dependent pressure vessel (DPV) designs. A CPV NiH2 battery, utilizing low-cost 64 mm (2.5 in.) cell diameter technology, has been designed and built for multiple smallsat programs, including the TUBSAT B spacecraft which is currently scheduled (24 Nov. 93) for launch aboard a Russian Proton rocket. An advanced 90 mm (3.5 in.) NiH2 cell design is currently being manufactured for the Space Station Freedom program. Prototype 254 mm (10 in.) diameter SPV batteries are currently under construction and initial boilerplate testing has shown excellent results. NiH2 cycle life testing is being continued at Eagle-Picher and IPV cells have currently completed more than 89,000 accelerated LEO cycles at 15% DOD, 49,000 real-time LEO cycles at 30 percent DOD, 37,800 cycles under a real-time LEO profile, 30 eclipse seasons in accelerated GEO, and 6 eclipse seasons in real-time GEO testing at 75 percent DOD maximum. Nickel-metal hydride battery development is continuing for both aerospace and electric vehicle applications. Eagle-Picher has also developed an extensive range of battery evaluation, test, and analysis (BETA) measurement and control equipment and software, based on Hewlett-Packard computerized data acquisition/control hardware.

Coates, Dwaine K.↗

Common/Dependent-Pressure-Vessel Nickel-Hydrogen Batteries

The term "common/dependent pressure vessel" (C/DPV) denotes a proposed alternative configuration for a nickelhydrogen battery. The C/DPV configuration is so named because it is a hybrid of two prior configurations called "common pressure vessel" (CPV) and "dependent pressure vessel" (DPV). The C/DPV configuration has been proposed as a basis for designing highly reliable, long-life Ni/H2-batteries and cells for anticipated special applications in which it is expected that small charge capacities will suffice and sizes and weights must be minimized.

Timmerman, Paul J.↗

On-Line, Real-Time Diagnostics of a Single Fluid Atomization System

A drop tube-Impulse Atomization technique was used to produce copper droplets. In this method, energy is transferred to a liquid by plunger movement resulting in spherical droplets emanating from orifices. A mathematical model of the evolution of droplet velocity and temperature at various heights for different sized droplets was developed. A two-color pyrometer, DPV-2000, and a shadowgraph were used to measure droplets radiant energy, diameter and velocity. The temperature values from the model were used to assess the two color pyrometer assumption over the temperature range of measurement. The DVP 2000 measurements were found to be dependent of droplet size wavelength and position of droplets below the atomizing nozzle. By calibrating the instrument for effective emissivity over the range of measurements, the thermal history of droplets may be recorded using a single color pyrometer approach.

DelshadKhatibi, P.↗