Engineering topics

Phillips, Wayne M.

Publications and source records attributed to Phillips, Wayne M..

7 records

NASA NTRS1998

Lifetime Modeling of Tin Electrodes for AMTEC Cells

In order to model the lifetime of the electrochemical cell in an Alkali Metal Thermal to Electric Converter (AMTEC), studies of TiN Electrodes on Beta-alumina solid electrolytes (BASE) have been made to determine the performace parameters over time. The first of a series of experiments in which TiN electrodes are studied in a Vapor Exposure Test Cell is described here, with preliminary results from electrochemical measurements made on the cell. The TiN electrodes tested here perform well, with minimal degradation over 1000 hours of operation at 850 degree C.

Electrochemical↗

NASA NTRS1997

Multi Band Gap High Efficiency Converter (Rainbow)

This papter reprots on the reexamination of the spectrally split, individually matched cell approach using modern-day optics and lightweight structures.

Converter Solar Array Efficiency Solar Spectrum↗

NASA NTRS1997

Loss of Alkali Oxide From Beta Alumina and its Importance to AMTEC Life Issues

Loss of sodium oxide into a gas phase comprises of low to high pressure sodium at typical AMTEC operating conditions does not seem indicated as a life limiting step under projected conditions.

Alkali Oxide AMTEC Sodium Oxide↗

NASA NTRS1995

Graphite-Fiber Heat Radiators

Heat radiators of proposed type feature thermally conductive fibers protruding from metallic surfaces to provide increased heat-dissipation surface areas. Free of leaks and more reliable than radiators incorporating heat pipes. Also lightweight and relatively inexpensive. Radial graphite fibers carry heat away from spherical shell and radiate heat into space. Radiators prove useful on Earth in special industrial and scientific applications involving dissipation of heat in vacuum or in relatively still air.

Phillips, Wayne M.↗

NASA NTRS1992

Manganese Nitride Sorption Joule-Thomson Refrigerator

Proposed sorption refrigeration system of increased power efficiency combines MnxNy sorption refrigeration stage with systems described in "Regenerative Sorption Refrigerator" (NPO-17630). Measured pressure-vs-composition isotherms for reversible chemisorption of N2 in MnxNy suggest feasibility to incorporate MnxNy chemisorption stage in Joule-Thomson cryogenic system. Discovery represents first known reversible nitrogen chemisorption compression system. Has potential in nitrogen-isotope separation, nitrogen purification, or contamination-free nitrogen compression.

Jones, Jack A.↗

NASA NTRS1991

Filament Winding Of Carbon/Carbon Structures

Improved method of winding carbon filaments for carbon/carbon composite structures less costly and labor-intensive, also produces more consistent results. Involves use of roller squeegee to ensure filaments continuously wet with resin during winding. Also involves control of spacing and resin contents of plies to obtain strong bonds between carbon filaments and carbon matrices. Lends itself to full automation and involves use of filaments and matrix-precursor resins in their simplest forms, thereby reducing costs.

Jacoy, Paul J.↗

NASA NTRS1990

Effects of heat treatment on carbon fibers

Commercially produced carbon fibers were heat treated to graphitization temperatures. The fibers were characterized for mechanical and physical properties, including density, D0002 spacing, strength, and modulus in both the 'as received' and heat treated conditions. Mechanical property changes were correlated with the physical property changes in the fibers.

Brown, D. Kyle↗