Search NASA⌕ Search

Engineering topics

Jordan, J. L.

Publications and source records attributed to Jordan, J. L..

15 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Understanding Calibration and Error Propagation in Longitudinal and Lateral Manganin Gauge Shock Experiments

Soda-lime glass remains elastic under shock pressures up to approximately 6.5 GPa. In this paper, soda lime glass shock experiments are used to understand the calibration and error propagation in longitudinal and lateral manganin gauge experiments. The errors in the calibration process for both longitudinal and lateral manganin gauge experiments are identified and discussed. Five soda-lime glass experiments up to 3 GPa are analyzed using this refined technique. The results show good agreement between the experimental data and the published calibration by Rosenberg and Moshel. Errors are propagated from the experimental data measurements and the assumptions that are made in the calibration, where the bulk of the error seems to come from uncertainty in the dynamic yield strength of manganin. Finally, the method presented in this paper allows for analysis of dynamic shock experiments with longitudinal and lateral manganin gauges including error propagation.

36 MATERIALS SCIENCE↗
NASA NTRS2015

Wireless Capacitive Pressure Sensor With Directional RF Chip Antenna for High Temperature Environments

This paper presents the design, fabrication and characterization of a wireless capacitive pressure sensor with directional RF chip antenna that is envisioned for the health monitoring of aircraft engines operating in harsh environments. The sensing system is characterized from room temperature (25 C) to 300 C for a pressure range from 0 to 100 psi. The wireless pressure system consists of a Clapp-type oscillator design with a capacitive MEMS pressure sensor located in the LC-tank circuit of the oscillator. Therefore, as the pressure of the aircraft engine changes, so does the output resonant frequency of the sensing system. A chip antenna is integrated to transmit the system output to a receive antenna 10 m away.The design frequency of the wireless pressure sensor is 127 MHz and a 2 increase in resonant frequency over the temperature range of 25 to 300 C from 0 to 100 psi is observed. The phase noise is less than minus 30 dBcHz at the 1 kHz offset and decreases to less than minus 80 dBcHz at 10 kHz over the entire temperature range. The RF radiation patterns for two cuts of the wireless system have been measured and show that the system is highly directional and the MEMS pressure sensor is extremely linear from 0 to 100 psi.

Pressure sensor↗
NASA NTRS1993

Helium-3 inventory of lunar samples: A potential future energy resource for mankind?

Recent public concern over the safety, cost, and environmental impact of the worldwide fission reactors has focused the attention of scientists and engineers towards perfecting fusion technology because it promises a much more environmentally acceptable 'clean' energy supply. The fusion reaction D-2 + He-3 yields p(14.7 MeV) + He-4(3.6 MeV) has long been recognized as an ideal candidate for producing commercially 'safer and cleaner' fusion power. Naturally occurring He-3 is scarce on earth; however, lunar regolith is a potential ore for He-3 because the high He-3 in solar wind has been implanted in the lunar regolith for more than 4 x 10(exp 9) years, along with other volatile species. The helium abundance in lunar soils is dependent not only on the maturity of soils (I(sub S)/FeO) but also on their mineralogy. The titanium-rich (ilmenite) lunar soils are important repositories for volatiles, which may be released by heating these soils up to approximately 700 C.

Murali, A. V.↗
NASA NTRS1992

Lunar hydrogen and other volatiles

The occurrence of solar wind implanted volatiles in the lunar regolith may provide resources to support a lunar settlement and fusion energy on earth in the 21st century. These volatiles include H, He, N, and C which are enriched in the finest fraction of the moon's comminuted regolith. These volatiles may be extracted by heating the soil. At 700 C near quantitative release of hydrogen and helium will occur, and approximately 20-30 percent of the N and C will corelease. It is estimated that per tonne of He-3 extracted from the lunar regolith at this temperature that 6300 tonnes H, 700 tonnes N, and 1600 tonnes C (as CO and CO2) will be released.

Jordan, J. L.↗
NASA NTRS1990

(Ar-39)-(Ar-40) dating of mesosiderites - Evidence for major parent body disruption less than 4 Ga ago

The (Ar-39) (Ar-40) chronologies were determined for 14 different mesosiderites representing the full range of classification according to recrystallization, and these chronologies were compared with analogous data for other meteorite types and for lunar highland rocks. Results of Ar-Ar chronologies indicate the history of a degassing of Ar due to a major thermal event that occurred less than 3.9 Ga ago; this event is not the metal-silicate mixing event, which is known to have occurred earlier than 4.4 Ga ago. It is suggested that a major collisional disruption-reassembly event less than 3.9 Ga ago took place, leaving the metal-silicate breccias buried under tens of kilometers of rubble, where they cooled slowly through the Ar closure temperatures.

Bogard, D. D.↗
NASA NTRS1989

Prediction of the He distribution at the lunar surface

Data on the contents of He and TiO2 and the maturity index, Is/FeO have been compiled, for all lunar soils for which measurements have been reported, in order to quantitatively asses the relationship between these parameters. The He content in lunar soils correlates approximately linearly with the product (Is/FeO)(TiO2 wt pct) over the range of measured values. The advantage of such a trend is the assistance it may provide in mapping the lunar surface for He and other solar-wind volatiles in a quantitative manner. A remote means of assessing Is/FeO in addition to TiO2 will be required.

Jordan, J. L.↗
NASA NTRS1986

Flight test report of the NASA icing research airplane: Performance, stability, and control after flight through natural icing conditions

Flight test results are presented documenting the effect of airframe icing on performance and stability and control of a NASA DHC-6 icing research aircraft. Kohlman System Research, Inc., provided the data acquisition system and data analysis under contract to NASA. Performance modeling methods and MMLE techniques were used to determine the effects of natural ice on the aircraft. Results showed that ice had a significant effect on the drag coefficient of the aircraft and a modest effect on the MMLE derived longitudinal stability coefficients (code version MMLE). Data is also presented on asymmetric power sign slip maneuvers showing rudder floating characteristics with and without ice on the vertical stabilizer.

Jordan, J. L.↗
NASA NTRS1986

The measurement of aircraft performance and stability and control after flight through natural icing conditions

The effects of airframe icing on the performance and stability and control of a twin-engine commuter-class aircraft were measured by the NASA Lewis Research Center. This work consisted of clear air tests with artificial ice shapes attached to the horizontal tail, and natural icing flight tests in measured icing clouds. The clear air tests employed static longitudinal flight test methods to determine degradation in stability margins for four simulated ice shapes. The natural icing flight tests employed a data acquisition system, which was provided under contract to NASA by Kohlman Systems Research Incorporated. This system used a performance modeling method and modified maximum likelihood estimation (MMLE) technique to determine aircraft performance degradation and stability and control. Flight test results with artificial ice shapes showed that longitudinal, stick-fixed, static margins are reduced on the order of 5 percent with flaps up. Natural icing tests with the KSR system corroborated these results and showed degradation in the elevator control derivatives on the order of 8 to 16 percent depending on wing flap configuration. Performance analyses showed the individual contributions of major airframe components to the overall degration in lift and drag.

Ranaudo, R. J.↗
NASA NTRS1977

Ar-40 intercept values and young apparent /K-40/-/Ar-40/ ages of five Apollo 15 fines

Correlations between Ar-40 and Ar-36 from size fractions of three Apollo 15 fines (15071, 15421, 15501) have been obtained. The Ar-40 intercept values of these fines and of 15091 and 15601 are generally lower than what one would expect for fines resulting from the comminution of rocks having ages of about 3.3 billion yr, typical for basalts of the landing site. This is interpreted to be the result of contamination by ray material from the Copernican age (equal or less than about 1 billion yr) craters, Autolycus and Aristillus, north of the landing site.

Jordan, J. L.↗
NASA NTRS1975

Light and dark soils at the Apollo 16 landing site

Lunar soils are discussed within the framework of a three-group classification scheme. Group I comprises North Ray Crater soils, group II contains light soils, and group III is made up of dark soils. It is suggested that group I soils originated from the light friable unit, one of the three units inside North Ray Crater. Group II soils were probably derived from the light matrix breccia unit; group II soils are mixtures of materials from all three units. It is concluded that soils with group III properties have been at the surface continuously for long periods. Group II soils show a record of solar wind exposure in the distant past (i.e., they have large (Ar-40/Ar-36)T ratios). Thus the regolith at the Apollo 16 site, which was observed to have marked layers of dark against light soils, contains sizeable 'pockets' or horizons at depth which are the sources of the group II soils.

Heymann, D.↗
NASA NTRS1975

Inert gases in fines at three levels of the trench at Van Serg Crater

Inert-gas measurements were conducted with three soil samples collected from a trench of about 17 cm depth which had been dug at Station 9, approximately 60-m southeast of the rim of Van Serg Crater on the moon. The particular trench is interesting because it is located in the continuous ejecta blanket of a relatively young crater. The results of the inert-gas measurements are presented in a table. They confirm an earlier conclusion reported by Heymann et al. (1974) that fines from Station 9 are among the most gas rich in the whole landing site. The three fines are agglutinate rich and most of the trapped gas is contained in the constructional particles. Agglutinate contents of fines tend to decrease rapidly for particles greater than about 250 micrometers.

Jordan, J. L.↗