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Dudzinski, T. J.

Publications and source records attributed to Dudzinski, T. J..

At least 19 records

Water vapor measurement system in global atmospheric sampling program, appendix

The water vapor measurement system used in the NASA Global Atmospheric Sampling Program (GASP) is described. The system used a modified version of a commercially available dew/frostpoint hygrometer with a thermoelectrically cooled mirror sensor. The modifications extended the range of the hygrometer to enable air sample measurements with frostpoint temperatures down to -80 C at altitudes of 6 to 13 km. Other modifications were made to permit automatic, unattended operation in an aircraft environment. This report described the hygrometer, its integration with the GASP system, its calibration, and operational aspects including measurement errors. The estimated uncertainty of the dew/frostpoint measurements was + or - 1.7 Celsius.

Englund, D. R.

NASA Global Atmospheric Sampling Program (GASP) data report for tape VL0014

The data currently available from GASP, including flight routes and dates, instrumentation, data processing procedures, and data tape specifications are described. Measurements of atmospheric ozone, cabin ozine, carbon monoxide, water vapor, particles, clouds, condensation nuclei, filter samples and related meteorological and flight information obtained during 562 flights of aircraft N533PA, N4711U, N655PA, and VH-EBE from October 3, 1977 through January 5, 1978 are reported. Data representing tropopause pressures obtained from time and space interpolation of National Meteorological Center archived data for the dates of the flights are included.

Briehl, D.

Carbon monoxide measurement in the global atmospheric sampling program

The carbon monoxide measurement system used in the NASA Global Atmospheric Sampling Program (GASP) is described. The system used a modified version of a commercially available infrared absorption analyzer. The modifications increased the sensitivity of the analyzer to 1 ppmv full scale, with a limit of detectability of 0.02 ppmv. Packaging was modified for automatic, unattended operation in an aircraft environment. The GASP system is described along with analyzer operation, calibration procedures, and measurement errors. Uncertainty of the CO measurement over a 2-year period ranged from + or - 3 to + or - 13 percent of reading, plus an error due to random fluctuation of the output signal + or - 3 to + or - 15 ppbv.

Dudzinski, T. J.

NASA Global Atmospheric Sampling Program (GASP) data report for tapes VL0011 and VL0013

In-situ measurements of atmospheric ozone, carbon monoxide, clouds, and related meteorological and flight information obtained during 1122 flights of aircraft VH-EBE and N655PA from January 10 through October 2, 1977 are reported. In addition, tropopause pressures obtained from time and space interpolation of achieved data for the dates of the flights are included.

Holdeman, J. D.

NASA Global Atmospheric Sampling Program (GASP) data report for tapes VL0010 and VL0012

The GASP atmospheric trace constituent data currently available are considered. Included on tapes are in-situ measurements of atmospheric ozone, carbon monoxide, water vapor, and clouds, data from laboratory analysis of filters exposed in flight, and related flight and meteorological data. Measurements of ozone levels within the first class cabin of these aircraft are also reported. In addition to the GASP data, tropopause pressures obtained from time and space interpolation of NMC archived data for the dates of the flights are included. Reported herein are the flight routes and dates, instrumentation, data processing procedures, data tape specifications, and analyses of the cabin ozone measurements.

Holdeman, J. D.

Airborne atmospheric sampling system

The atmospheric sampling system developed for use on board commercial airliners as part of the Global Atmospheric Sampling Program (GASP) is described. The automated air-constituent measuring system is installed in a Boeing 747 airliner below the passenger cabin floor near the nose wheel well. It consists of an air sample flow system, composed of air inlet and pressurization systems, computerized data acquisition and system control units which direct system operation in 15 modes, and commercial instruments significantly modified to measure low levels of atmospheric constituents (ozone, water vapor, nitrogen oxides, carbon monoxide, chlorofluoromethanes, particulates, condensation nuclei, sulfates and nitrates). Flight and meteorological data, including air temperature and altitude, are also recorded. The system is designed for servicing at 14-day intervals, and to require a minimum of aircrew involvement.

Gustafsson, U. R. C.

NASA Global Atmospheric Sampling Program (GASP) data report for tape VL0009

The GASP atmospheric trace constituent data cover atmospheric ozone, carbon monoxide, condensation nuclei, clouds, and related meteorological and flight information obtained during October 28-31, 1977. Reported herein are flight routes and dates, instrumentation, data processing procedures, and data tape specifications.

Holdeman, J. D.

Total-pressure measurement in pulsating flows

Pneumatic-type probe was used as comparison instrument with total pressure tubes to determine true average pressure and, thus, to determine if nonlinear averaging effects were significant. Since pneumatic probe is more complicated to use than a total-pressure tube, it is used only as a comparison instrument to determine extent of averaging effects.

Krause, L. N.

Total-pressure averaging in pulsating flows.

A number of total-pressure tubes were tested in a nonsteady flow generator in which the fraction of period that pressure is a maximum is approximately 0.8, thereby simulating turbomachine-type flow conditions. Most of the tubes indicated a pressure which was higher than the true average. Organ-pipe resonance which further increased the indicated pressure was encountered with the tubes at discrete frequencies. There was no obvious combination of tube diameter, length, and/or geometry variation used in the tests which resulted in negligible averaging error. A pneumatic-type probe was found to measure true average pressure and is suggested as a comparison instrument to determine whether nonlinear averaging effects are serious in unknown pulsation profiles.

Krause, L. N.

A probe for measuring temperature and pressure at the same points in a gas stream

Design features and characteristics of a means for measuring total temperature and total pressure at a single point in a gas stream are presented. A rake that provides five such combination measurements is described. Experimental data are included for the aerodynamic recovery and time response of the temperature sensor and for the flow-angle sensitivity of both the temperature and pressure sensors. Data were obtained over a subsonic Mach number range of 0.3 to 0.9 as well as at a Mach number of 1.4.

Krause, L. N.

Total pressure averaging in pulsating flows

A number of total-pressure tubes were tested in a non-steady flow generator in which the fraction of period that pressure is a maximum is approximately 0.8, thereby simulating turbomachine-type flow conditions. Most of the tubes indicated a pressure which was higher than the true average. Organ-pipe resonance which further increased the indicated pressure was encountered within the tubes at discrete frequencies. There was no obvious combination of tube diameter, length, and/or geometry variation used in the tests which resulted in negligible averaging error. A pneumatic-type probe was found to measure true average pressure, and is suggested as a comparison instrument to determine whether nonlinear averaging effects are serious in unknown pulsation profiles. The experiments were performed at a pressure level of 1 bar, for Mach number up to near 1, and frequencies up to 3 kHz.

Krause, L. N.

Flow direction measurement with fixed probes

Fixed-position probes for determination of flow direction in one and two planes are tested over a wide range of Reynolds numbers and Mach numbers. The work is limited to tests of a single probe design for two dimensional flow and a single design for three dimensional flow.

Dudzinski, T. J.