Investigation of neutron transmission through shielding by means of unidirectional sources /the B-2 installation/
Unidirectional radiation sources for determining neutron distribution through nuclear reactor shielding
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Unidirectional radiation sources for determining neutron distribution through nuclear reactor shielding
Scintillation counters for measuring gamma radiation of tracers in nuclear reactor shielding studies
Measuring fast neutron fluxes in nuclear shielding on background of intense intermediate neutron fluxes
Experimental and theoretical studies in spectroscopy and transport problems of electron shielding
Radiative ceramic heat shield designs for manned lifting entry vehicles
Heat shield efficiency over plane surface during injection through two tangential slots studied in wind tunnel
Ultrasonic techniques for nondestructive testing for Saturn honeycomb heat shields
Sensitive magnetic susceptibility measurements using superconducting circuits and magnetic shields
Magnetic shielding properties of earth mantle obtained from power spectrum, deducing transfer function of mantle
Reflectance of pyrolytic graphite and phenolic nylon chars for radiant heat rejection from nonablating heat shield
Hypersonic trim angle of attack of lifting entry vehicles, correlating stagnation point values obtained from heat shield ablation and pressure distribution measurements
Event recorder for in-flight measurements of missile heat-shield ablation
The purpose of this testing is to determine the suitability of trivalent chromium conversion coatings that meet the requirements of MIL-DTL-5541, Type II, for use in applications where high-frequency electrical performance is important. This project will evaluate the ability of coated aluminum to form adequate EMI seals. Testing will assess performance of the trivalent chromium coatings against the known control hexavalent chromium MIL-DTL-5541 Type I Class 3 before and after they have been exposed to a set of environmental conditions. Performance will be assessed by evaluating shielding effectiveness (SE) test data from a variety of test samples comprised of different aluminum types and/or conversion coatings.
Heat-shield for Extreme Entry Environment Technology (HEEET) has been in development since 2014 with the goal of enabling missions to Venus, Outer Planets, and high-speed sample return missions. It is nearing successful completion and will be delivered by March of 2019. The 15 min presentation at the VEXAG will report on the HEEET development completed to-date and remaining testing and documentations prior to delivery of a TRL 6 technology.
Previous missions have subjected astronauts to confined space, weightlessness, and increased radiation. These impair astronaut comfort, performance, and future health. The exploration and future settlement of space will depend on the long-term presence of individual humans. This requires the development of space platforms where humans can work and live in health for many years, perhaps generations. A livable space platform must provide adequate volume, gravity, and radiation shielding. This seems easier to do in deep space or Low Earth Orbit (LEO) than on the surface of the moon or Mars. Permanently habitable deep space platforms will enable scientific and technical research, space tourism, space mission preparation, space industry development, and military surveillance and operations. The first fully habitable space station would probably be in LEO for convenience and lower cost.
This project looked at optimizing the dielectric cover layer on top of an optically clear glass electrodynamic dust shield (EDS). The EDS is a device that uses high voltage electric fields to remove dust from surfaces. Currently, the EDS uses 2000 volts to remove dust, but by optimizing the cover layer and the geometry of the EDS, this voltage can be lowered to improve safety and reduce electromagnetic interference (EMI) and the complexity of supporting systems. This project was able to demonstrate successful dust clearing on an EDS with 750 volts in high vacuum (~1E-5 torr) conditions. The EDS had a trace spacing of 500 μm, and the Parylene C cover layer had a thickness of 25 μm. There is still a substantial amount of room for improvement of these devices, which may be able to push the operating voltage even lower.
Electric field attenuation measurements for radio frequency shielded equipment
High energy electron radiation effect on optical transmission of transparent materials for solar cell shields