Search NASA⌕ Search

SEARCH · Search NASA

Results for “probing”

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.

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

At least 1,081 records · Page 60
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Flight experience with a pivoting traversing boundary-layer probe

A pivoting traversing boundary layer probe was evaluated in flight on an F-104 airplane. The evaluation was performed at free stream Mach numbers from 0.8 to 2.0. The unit is described, and operating problems and their solutions are discussed. Conventional boundary layer profiles containing variations in flow angle within the viscous layer are shown for free stream Mach numbers of 0.8, 1.6, and 2.0. Although the unit was not optimized for size and weight, it successfully measured simultaneously flow angularity, probe height, and pitot pressure through the boundary layer.

Montoya, L. C.↗
NASA NTRS1973

Iterative methods for plasma sheath calculations: Application to spherical probe

The computer cost of a Poisson-Vlasov iteration procedure for the numerical solution of a steady-state collisionless plasma-sheath problem depends on: (1) the nature of the chosen iterative algorithm, (2) the position of the outer boundary of the grid, and (3) the nature of the boundary condition applied to simulate a condition at infinity (as in three-dimensional probe or satellite-wake problems). Two iterative algorithms, in conjunction with three types of boundary conditions, are analyzed theoretically and applied to the computation of current-voltage characteristics of a spherical electrostatic probe. The first algorithm was commonly used by physicists, and its computer costs depend primarily on the boundary conditions and are only slightly affected by the mesh interval. The second algorithm is not commonly used, and its costs depend primarily on the mesh interval and slightly on the boundary conditions.

Parker, L. W.↗
NASA NTRS1973

Lunar neutron probe experiment

Preliminary results of the Apollo 17 neutron probe are presented. The probe which was designed for measuring neutron capture rates to a depth of 2m in the lunar regolith is described, and the fission rates for U-235 are discussed. It is concluded that good agreement exists between the experimental results and theoretical calculations.

Woolum, D. S.↗
NASA NTRS1972

Wind speeds in lower atmosphere of Venus: Status report on possible measurement via differential VLBI tracking of entry probes

The potential of very-long-baseline interferometry (VLBI) is examined for use in the determination of wind speeds in Venus' lower atmosphere via the differential tracking of entry probes. A simplified mathematical model is presented in detail. An incomplete error analysis based on this model permits an educated guess to be made: an uncertainty in wind speed determination of no more than about 100/t m/sec, where t l is the corresponding time resolution in seconds, is an achievable goal, without the use of transponders on the miniprobes. If transponders are available on all probes, there should be little difficulty in estimating wind speeds with useful precision.

Shapiro, I. I.↗
NASA NTRS1974

Microstrip antenna study for Pioneer Saturn/Uranus atmosphere entry probe

The design parameters of a microstrip antenna were studied to determine its performance characteristics as affected by an atmospheric entry probe environment. The technical literature was reviewed to identify the known design and performance characteristics. These data were used to evaluate the expected effects of mission environments on the microstrip antenna design proposed for the Saturn/Uranus Atmospheric Entry Probe (SAEP). Radiation patterns and VSWR measurements were made to evaluate the performance in the SAEP thermal environment. Results of the literature search and pattern tests confirm that the microstrip antenna is a good choice as a transmitting antenna on the SAEP. The microstrip antenna is efficient, compact, and well suited to a space environment. The pattern can be controlled with a minimum beamwidth of 60 degrees (air substrate; e.g., honeycomb structure) and a maximum on the order of 100 degrees with higher dielectric constant substrates. The power handling capacity is good and can be improved by covering the antenna with a dielectric cover.

Kuhlman, E. A.↗
NASA NTRS1973

Hot-wire coil probe for high-speed flows

Small-diameter-wire coil probes developed for use in a hypersonic helium tunnel are discussed. The springlike properties of the coil minimize strain-gauge effects, and allow to use a higher length-to-diameter ratio for a given flow. In addition, the coil is more rugged for sudden flow changes, and since it can be mounted straight across the support tips, there is less support interference in cross flows. In addition to measuring fluctuating quantities in a boundary layer, the probes were used with a constant temperature anemometer for measuring mean mass flow profiles, and with a constant current anemometer for measuring mean total temperature profiles.

Weinstein, L. M.↗
NASA NTRS1974

The navigation of space probes

A new navigational method combining electronic measurement procedures and celestial mechanics makes it possible to conduct a space probe very close to a desired point in the neighborhood of a remote planet. Approaches for the determination of the position of the space probe in space are discussed, giving attention to the effects of errors in the employed data. The application of the navigational methods in a number of space missions is also considered.

Fliegel, H. F.↗
NASA NTRS1974

Miniature probes for use in gas turbine testing

Several examples of miniature probes (null type as well as fixed position) are presented which have proved useful in aircraft and space power systems component testing and are applicable to automotive gas turbine testing. These probes are used to determine component or system performance from the measurement of gas temperature as well as total and static pressure, and flow direction. Detailed drawings of the sensors are presented along with experimental data covering the flow characteristics over the range of intended use.

Glawe, G. E.↗
NASA NTRS1974

Heavy ion beam probe measurements of radial potential profiles in the modified Penning discharge

A heavy ion beam probe was used to examine the radial potential profile of a plasma in the modified Penning discharge. The plasma has strong (approximately kV) electrostatic potentials near the anode ring which can be a large fraction of the injected ion beam energy. A primary (singly ionized) thallium ion beam is injected through the plasma in the midplane of a double Penning anode ring. After passage through the plasma, primary and secondary (doubly ionized) ions are detected with either a set of flat probes or an electrostatic energy analyzer. A calculation of the primary orbit through the plasma is performed to obtain an approximation to the measured primary beam trajectory. As the real radial potential profile is unknown, an adjustable model is used in the computer program. The adjustable potential profile is varied until the best agreement between measured and calculated trajectories is obtained. Secondary orbits are also predicted using the best fitting adjustable profile. The calculations indicate that secondary beams originating at more than one point in the plasma can be simultaneously observed at the electrostatic analyzer with certain primary beam initial conditions.

Kambic, G. X.↗
NASA NTRS1973

Saturn Uranus atmospheric entry probe mission spacecraft system definition study

The modifications required of the Pioneer F/G spacecraft design for it to deliver an atmospheric entry probe to the planets Saturn and Uranus are investigated. It is concluded that it is feasible to conduct such a mission within the constraints and interfaces defined. The spacecraft required to perform the mission is derived from the Pioneer F/G design, and the modifications required are generally routinely conceived and executed. The entry probe is necessarily a new design, although it draws on the technology of past, present, and imminent programs of planetary atmospheric investigations.

Source record↗
NASA NTRS1974

Outer planet probe navigation

A series of navigation studies in conjunction with outer planet Pioneer missions are reformed to determine navigation requirements and measurement systems in order to target probes. Some particular cases are established where optical navigation is important and some cases where radio alone navigation is suffucient. Considered are a direct Saturn mission, a Saturn Uranus mission, a Jupiter Uranus mission, and a Titan probe mission.

Friedman, L.↗
NASA NTRS1974

Pioneer Venus probe design

The summary provides descriptions for a set of probes designed to explore an inner rather than an outer planet, and designed to survive to 100 bars rather than 10 bars. The probes carry a variety of scientific instruments and their supporting integrated subsystems are adjusted to Venus environmental conditions.

Nolte, L. J.↗
NASA NTRS1974

Probe interface design consideration

Interface design between a probe and a spacecraft requires not only technical considerations but also management planning and mission analysis interactions. Two further aspects of importance are the flyby versus the probe trade-off, and the relay link design and data handling optimization.

Casani, E. K.↗
NASA NTRS1974

Probe design and system integration

The feasibility of a common Saturn Uranus probe design is studied by considering the extreme atmospheres of both planets and their effects on a Pioneer spacecraft. It seems that approximately 85 percent of existing hardware can be used in an Uranus probe design, assuming that the design entry g level is somewhat reduced from current requirements. Additional development efforts include heat shielding, remotely activated batteries, mass spectrometer optimization, thermal insulation materials and high g packaging concepts.

Carroll, P.↗
NASA NTRS1974

Carbon phenolic heat shields for Jupiter/Saturn/Uranus entry probes

Carbon phenolic heat shield technology is reviewed. Heat shield results from the outer planetary probe mission studies are summarized along with results of plasma jet testing of carbon phenolic conducted in a ten megawatt facility. Missile flight data is applied to planetary entry conditions. A carbon phenolic heat shield material is utilized and tailored to accommodate each of the probe missions. An integral heat shield approach is selected over in order to eliminate a high temperature interface problem and permit direct bonding of the carbon phenolic to the structural honeycomb sandwich. The sandwich is filled with a very fine powder to minimize degradation of its insulation properties by the high conductive hydrogen/helium gases during the long atmospheric descent phase.

Mezines, S.↗
NASA NTRS1974

Cloud detecting nephelometer for the Pioneer-Venus probes

Design specifications of a cloud detecting nephelometer for the Pioneer-Venus probe are given. The instrument is designed to measure the presence of clouds, their vertical structure or extent, and from the multiple probe data, provide some guides as to the global variability of the cloud structure. Specifications for the instrument include the ability to operate in the near ultraviolet, visible, and near infrared wavelengths, monitor optical quality of windows and temperatures of critical components, operate at altitudes of less than or equal to 300 m.

Ragent, B.↗
NASA NTRS1974

Thermal control for planetary probes

Thermal control of planetary probes during the descent phase of a mission is examined. Emphasis was placed on the problems of atmospheric uncertainties to be encountered by the probes, insulation performance, and equipment temperature limits.

Mcmordie, R.↗
NASA NTRS1974

Proceedings: Outer Planet Probe Technology Workshop, summary volume

A summary report and overview of the Outer Planet Probe Technology Conference are given. Summary data cover: (1) state of the art concerning mission definitions, probe requirements, systems, subsystems, and mission peculiar hardware, (2) mission and equipment trade-offs associated with Saturn/Uranus baseline configuration and the influence of Titan and Jupiter options on mission performance and costs, and (3) identification of critically required future R and D activities.

Source record↗