Radiative transfer in the mesosphere
Radiative temperature changes for molecular gases under non local thermodynamic equilibrium
Kuhn, W.↗
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An Analog Computer Study of the Low-Frequency Flow Dynamics of Two Nuclear-Rocket Cold-Flow Engine Systems
An analog computer study is made of the low-frequency flow dynamics observed with liquid hydrogen flowing in two different nuclear-rocket cold-flow (unfueled) engine systems. The prediction of the low-frequency response depends largely upon the generation of the proper mass-flow storage in the system. This is achieved by relating, in the model lumping, the average values of fluid enthalpy and a certain thermodynamic fluid property. A two-phase state equation is derived for thermodynamic equilibrium between the gas and liquid phases. Parametric studies are made which demonstrate the effect of the pump characteristics on the flow damping.
Fox, Harry W., Jr.↗
The chemical composition of normal stellar atmospheres.
Chemical composition of stellar atmospheres by model atmospheres, considering atomic transition, line broadening and thermodynamic equilibrium
Aller, L. H.↗
Shock-tube thermochemistry tables for high- temperature gases, 90% carbon dioxide and 10% nitrogen, volume 2
Shock tube tabulated computer equilibrium thermodynamic properties for carbon dioxide and nitrogen mixture
Horton, T. E.↗
Heat transfer in the convective envelope of the sun
Heat transfer in solar convective layer derived by thermodynamic equilibrium and proton transport methods
Schocken, K.↗
Structure of the blast wave with ionization
Plane, cylindrical and spherical blast waves structure with ionization at local thermodynamic equilibrium analyzed using successive approximation to nonsimilar solution
Fu, T. S.↗
Thermodynamic equilibria from plasma sources. III - Carbon-hydrogen-nitrogen systems
Product distribution of organic nitrogen compounds plasma sources computed by assuming high temperature limited thermodynamic equilibrium
Griffiths, P. R.↗
Reaction constants in the system Fe-MgO-SiO2-O2 at 1 atm between 900 and 1300 C - Experimental results
Thermodynamic equilibrium constants of Fe-MgO-SiO2-O2 system reactions at one atmosphere and 900-1300 C
Williams, R. J.↗
Absorption coefficients for hydrogen. II - Calculated pressure-induced H2-H2 vibrational absorption in the fundamental region
Pressure induced hydrogen collisions vibrational spectra absorption coefficients at high temperatures and local thermodynamic equilibrium
Patch, R. W.↗
Earth physics and phase transformations program: A concept and proposal
A program to study the geophysical characteristics of the earth is presented as an integration of the different disciplines that constitute the earth sciences, through the foundation of a generalized geodynamic theory of earth physics. A program is considered for defining the physical constants of the earth's material which parametrize the hydrodynamic equation in the microscopic solid state behavior of the crystals of the lithosphere. In addition, in order to lay the foundation for a generalized theory in earth physics, specific research areas are considered, such as the nature of the kinetics of the phase transitions in mineral assemblages, the equilibrium thermodynamic properties of crystals which are major constituents of mineral assemblages, and the transport properties of pure crystals which are major constituents of mineral assemblages.
Bonavito, N. L.↗
Vacuum ultraviolet radiometry with a stabilized hydrogen arc.
Use of the spectral radiation emitted from a dense hydrogen plasma of at least 12,000 K, which is in local thermodynamic equilibrium (LTE), as a light source for vacuum UV radiometry. Its spectroscopic qualities are exactly known, and except for a few strongly Stark-broadened Lyman lines, its spectrum in the vacuum UV is essentially continuous. The calculated continuum output of this source for typical operating conditions is compared with the UV output of the tungsten strip lamp and the carbon arc.
Ott, W. R.↗
Origin of strong magnetic fields.
A possible mechanism by which extremely strong magnetic fields in neutron stars and white dwarfs could originate involves the existence of thermodynamic equilibrium states (LOFER states) of an electron gas. The essence of the stability theory of a LOFER state is discussed. The extended electronic system considered is in contact with a thermal bath in the presence of an external magnetic field. It is found that it is not necessary to require absolute stability in order to realize a LOFER state in nature.
Canuto, V.↗
Simplified method for measuring mean opacities and effective absorption coefficients.
Use of wide bandwidths and a number of path lengths to obtain mean opacities and effective absorption coefficients. This method is applicable if the temperatures and pressures at which these qualities are desired can be duplicated experimentally. Additional restrictions are that the gas in the experiments must be essentially isothermal, homogeneous, nonscattering, and in local thermodynamic equilibrium. The method is most advantageous in shock tube experiments and experiments utilizing a pulsed arc of cylindrical symmetry viewed axially.
Patch, R. W.↗
Comparison of measured and theoretical inverse bremsstrahlung and photoionization absorption of infrared radiation in a H-He plasma.
The absorption coefficients of 1.15- and 3.39-micrometer radiation for a homogeneous H-He plasma have been measured in a temperature and electron density range where the major absorption mechanisms are electron-ion inverse bremsstrahlung and neutral-atom photoionization. Measurements were made behind both the incident and reflected shock waves in a driven tube by recording the laser intensity transmitted along the tube diameter as a function of time. The measured values compare well with those obtained from theoretical calculations for a gas in thermodynamic equilibrium.
Billman, K. W.↗
On the observability of the H3/+/ fundamental spectrum.
The calculations and conclusions of Kawaoka and Borkman (1971) concerning the dipole moment derivative of the H3(+) electronic ground state are discussed. The possibility of observing the H3(+) fundamental in hydrogen gas in local thermodynamic equilibrium is considered, and the H3(+) average absorption coefficient is compared with the total absorption coefficient for other mechanisms.
Patch, R. W.↗
Cavitation in liquid cryogens. 2: Hydrofoil
Boundary layer principles, along with two-phase concepts, are used to improve existing correlative theory for developed cavity data. Details concerning cavity instrumentation, data analysis, correlative techniques, and experimental and theoretical aspects of a cavitating hydrofoil are given. Both desinent and thermodynamic data, using liquid hydrogen and liquid nitrogen, are reported. The thermodynamic data indicated that stable thermodynamic equilibrium exists throughout the vaporous cryogen cavities. The improved correlative formulas were used to evaluate these data. A new correlating parameter based on consideration of mass limiting two-phase flow flux across the cavity interface, is proposed. This correlating parameter appears attractive for future correlative and predictive applications. Agreement between theory and experiment is discussed, and directions for future analysis are suggested. The front half of the cavities, developed on the hydrofoil, may be considered as parabolically shaped.
Hord, J.↗
Cavitation in liquid cryogens. 3: Ogives
Experimental results for three, scaled, quarter-caliber ogives are given. Both desinent and developed cavity data, using liquid hydrogen and liquid nitrogen, are reported. The desinent data do not exhibit a consistent ogive size effect, but the developed cavity data were consistently influenced by ogive size; B-factor increases with increasing ogive diameter. The developed cavity data indicated that stable thermodynamic equilibrium exists throughout the vaporous cavities. These data were correlated by using the extended theory derived in NASA-CR-2156 (volume II of this report series). The new correlating parameter MTWO, improves data correlation for the ogives, hydrofoil, and venturi and appears attractive for future predictive applications. The cavitation coefficient and equipment size effects are shown to vary with specific equipment-fluid combinations. A method of estimating cavitation coefficient from knowledge of the noncavitating pressure coefficient is suggested.
Hord, J.↗
Calculation of 5250.216 A line profiles in sunspots.
It is shown that spectral line profiles, used in the calibration and interpretation of magnetograph results, cannot be considered as reliable when they are calculated under the assumption of pure absorption and local thermodynamic equilibrium, frequently employed. Because of this assumption, the line-to-continuous absorption ratio becomes very large at the top of the sunspot model, causing the emergent intensity to originate at a very shallow depth in the sunspot. This is illustrated by calculations of the Fe I 5250.2 A line for three sunspot models.
Dunn, A. R.↗