Current drainage to a high voltage probe in a dilute plasma
Electron drainage current from dilute plasma through holes in high voltage dielectric probes
Grier, N. T.↗
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Experimental determination of pressure drop and flow characteristics of dilute gas-solid suspensions
Experimental determination of pressure drop and flow characteristics of dilute gas-solid suspensions in turbulent pipe flow
Pfeffer, R.↗
Flow dilution effect on blood coagulation in vivo
Enzyme reaction model of flow dilution effect on blood coagulation in vivo
Hu, C.↗
Aluminium. II - A review of deformation properties of high purity aluminium and dilute aluminium alloys.
The elastic and plastic deformation behavior of high-purity aluminum and of dilute aluminum alloys is reviewed. Reliable property data, including elastic moduli, elastic coefficients, tensile, creep, fatigue, hardness, and impact are presented. Single crystal tensile results are discussed. Rather comprehensive reference lists, containing publications of the past 20 years, are included for each of the above categories. Defect structures and mechanisms responsible for mechanical behavior are presented. Strengthening techniques (alloys, cold work, irradiation, quenching, composites) and recovery are briefly reviewed.
Reed, R. P.↗
Evaluation of an experimental short-length annular combustor: One-side-entry dilution airflow concept
A test program was conducted to evaluate an experimental short-length annular combustor that uses a one-side-entry dilution airflow concept. The combustor design features scoops on the outer liner for controlling the primary- and secondary-zone airflow distribution. Combustor inlet total pressures were limited to 62 N/sq cm (90 psia) with inlet-air temperatures from 590 K (600 F) to 890 K (1150 F). At a diffuser inlet Mach number of 0.25, the exit temperature pattern factor was 0.44 with an average exit temperature of 1436 K (2124 F) and a total pressure loss of 4.3 percent. At a diffuser inlet Mach number of 0.31, the exit temperature pattern factor was reduced to 0.29 with an average exit temperature of 1450 K (2151 F) and a total pressure loss of 6.1 percent. Nominal combustion efficiencies of 100 percent were obtained with the ASTM A-1 fuel. Exhaust gas emissions, smoke, and altitude relight data are included with exit-temperature profiles and distribution patterns.
Humenik, F. M.↗
Characteristics of dilute gas-solids suspensions in drag reducing flow
Measurements were performed on dilute flowing gas-solids suspensions and included data, with particles present, on gas friction factors, velocity profiles, turbulence intensity profiles, turbulent spectra, and particle velocity profiles. Glass beads of 10 to 60 micron diameter were suspended in air at Reynolds numbers of 10,000 to 25,000 and solids loading ratios from 0 to 4. Drag reduction was achieved for all particle sizes in vertical flow and for the smaller particle sizes in horizontal flow. The profile measurements in the vertical tube indicated that the presence of particles thickened the viscous sublayer. A quantitative theory based on particle-eddy interaction and viscous sublayer thickening has been proposed.
Kane, R. S.↗
Dispersion and dilution of jet aircraft exhaust at high-altitude flight conditions
A method is presented for estimating the dispersion and dilution of jet aircraft exhaust from aircraft passage through times on the order of weeks thereafter. In the near wake of the aircraft, the solution is that for round turbulent jets in a parallel flow. More rapid dispersion due to atmospheric effects begins when the scale-dependent eddy viscosity becomes larger than the turbulent jet eddy viscosity. In the far wake region, the solution approaches that for scale-dependent dispersion from a point source moving with the aircraft. Calculations are presented for supersonic aircraft at high altitude flight conditions.
Holdeman, J. D.↗
The diluter-demand oxygen system used during the international Himalayan expedition to Mount Everest.
The diluter-demand regulators are designed in such a way that as the individual inspires he simultaneously draws ambient air and pure oxygen from a tank into his mask. The size of the ambient air orifice is made directly proportional to the barometric pressure by use of a passive aneroid valve. As altitude increases the ambient air orifice is automatically made smaller and the individual inspires a greater proportion of oxygen.
Blume, F. D.↗
Mechanical properties of electron-beam-melted molybdenum and dilute Mo-Re alloys.
Study of Mo-Re alloys aimed at examining the effects of small rhenium additions on the low-temperature ductility of molybdenum and determining the mechanical properties of dilute Mo-Re alloys. The results obtained indicate that high-purity Mo-Re alloys have ductile-brittle transition temperatures considerably lower than those for unalloyed molybdenum and that rhenium promotes normal solid-solution strengthening in molybdenum at elevated temperatures.
Klopp, W. D.↗
Dispersion and dilution of jet aircraft exhaust at high-altitude flight conditions
A method is presented for estimating the dispersion and dilution of jet aircraft exhaust from aircraft passage through times on the order of weeks thereafter. In the near wake of the aircraft, the solution is that for round turbulent jets in a parallel flow. More rapid dispersion due to atmospheric effects begins when the scale-dependent eddy viscosity becomes larger than the turbulent jet eddy viscosity. In the far wake region, the solution approaches that for scale-dependent dispersion from a point source moving with the aircraft. Calculations are presented for supersonic aircraft at high-altitude flight conditions.
Holdeman, J. D.↗
Automated measurement of respiratory gas exchange by an inert gas dilution technique
A respiratory gas analyzer (RGA) has been developed wherein a mass spectrometer is the sole transducer required for measurement of respiratory gas exchange. The mass spectrometer maintains all signals in absolute phase relationships, precluding the need to synchronize flow and gas composition as required in other systems. The RGA system was evaluated by comparison with the Douglas bag technique. The RGA system established the feasibility of the inert gas dilution method for measuring breath-by-breath respiratory gas exchange. This breath-by-breath analytical capability permits detailed study of transient respiratory responses to exercise.
Sawin, C. F.↗
Investigation of effects of background water on upwelled reflectance spectra and techniques for analysis of dilute primary-treated sewage sludge
In an effort to improve understanding of the effects of variations in background water on reflectance spectra, laboratory tests were conducted with various concentrations of sewage sludge diluted with several types of background water. The results from these tests indicate that reflectance spectra for sewage-sludge mixtures are dependent upon the reflectance of the background water. Both the ratio of sewage-sludge reflectance to background-water reflectance and the ratio of the difference in reflectance to background-water reflectance show spectral variations for different turbid background waters. The difference in reflectance is the only parameter considered.
Whitlock, C. H.↗
Hydrogen chloride partitioning in a Titan III exhaust cloud diluted with ambient air
Measurements and analysis are presented of the partitioning of HCl between hydrochloric acid aerosol and gaseous HCl in a Titan III exhaust cloud, as the cloud is diluted with humid ambient air. Partitioning was determined by measuring the gaseous HCl concentration with a recently developed airborne Gas Filter Correlation detector and simultaneously with a chemiluminescence detector which measures total HCl. Although equilibrium predictions for HCl aerosol formation indicated that no HCl aerosol should exist in the exhaust cloud for the meteorological conditions of this launch, the measurements indicated significant HCl aerosol formation. These measurements will provide verification for advanced modeling programs now under development.
Sebacher, D. I.↗
Geometric dilution of precision in Global Positioning System navigation
The evaluation of the GPS navigation performance is essentially equivalent to the computation of the diagonal terms of the geometric dilution of precision (GDOP) matrix. Certain theoretical results concerning the general properties of the GDOP matrix are obtained. An efficient algorithm for the computation of the GDOP matrix and the navigation performance index is given; and applications of the results are illustrated by numerical examples.
Fang, B. T.↗
Muon hyperfine fields in iron and its dilute alloys
The temperature dependence of the interstitial magnetic field, B, as determined by the rotation of the spin of the muon, has been measured for dilute polycrystalline iron alloys with Mo, Ti, and Nb additions over a temperature range of 240 to 633 K. In all cases the behaviors differ from one another and from the Fe(Al) alloys previously studied. B, which is negative with respect to the magnetization, is increased in magnitude by Al and Mo, and decreased greatly by Ti. The addition of Nb creates a two-phase alloy from which the role of heterogeneity and/or strain on B in iron can be assessed. If the temperature dependence of the hyperfine field extracted from B for Fe(Mo) alloys is interpreted on the model previously used to discuss the Fe(Al) data, then the muon must be attracted to the Mo atom while repelled by the Al atoms as the temperature decreases.
Stronach, C. E.↗
Dilution Jet Mixing Program, phase 1
The effect of jet to mainstream density ratio, flow area convergence as encounted in transition sections, and nonuniform mainstream profile upstream of dilution orifices on the mixing of a row of jets with a confined cross flow was quantified. It is found that: (1) jet spreading rate in transverse direction is increased with increasing J, H/D and with decreasing S/D; (2) the density ratio has only a second order effect on the jet mixing characteristics for a constant momentum ratio; (3) the temperature distributions in the jet mixing region are strongly influenced by the undisturbed mainstream profile; (4) flow area convergence enhances mixing in radial and transverse directions. An asymmetric convergent duct with flat wall injection has the same jet mixing characteristics as a symmetric convergent duct. An asymmetric convergent duct with slant wall injection has a faster jet spreading rate in the transverse direction.
Srinivasan, R.↗
ECUT: Energy Conversion and utilization Technologies program biocatalysis research activity. Generation of chemical intermediates by catalytic oxidative decarboxylation of dilute organic acids
A rhodium-based catalyst was prepared and preliminary experiments were completed where the catalyst appeared to decarboxylate dilute acids at concentrations of 1 to 10 vol%. Electron spin resonance spectroscoy was used to characterize the catalyst as a first step leading toward modeling and optimization of rhodium catalysts. Also, a hybrid chemical/biological process for the production of hydrocarbons has been assessed. These types of catalysts could greatly increase energy efficiency of this process.
Distefano, S.↗
Dilution Zone Mixing
Studies to characterize dilution zone mixing; experiments on the effects of free-stream turbulence on a jet in crossflow; and the development of an interactive computer code for the analysis of the mixing of jets with a confined crossflow are reviewed.
Holdeman, J. D.↗