Turbulent boundary layer on a rotating disk calculated with an effective viscosity
Skewed turbulent boundary layer and incompressible laminar flow on rotating disk, considering effective viscosity relations and applications domain
Cooper, P.↗
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A two-component model of the quiet solar wind with viscosity, magnetic field, and reduced heat conduction
Quiet solar wind two component model, including viscosity, magnetic field and reduced heat conduction
Brandt, J. C.↗
Eddy viscosity distributions in a Mach 20 turbulent boundary layer
Shear stress and eddy viscosity distribution in Mach 20 compressible turbulent boundary layer, using mixing length flow theory
Bushnell, D. M.↗
Rarefied-gas viscoseal
Sealing coefficient and leakage performance model for multiple thread rarefied gas viscoseals
Milligan, M. W.↗
Mineralogy-petrology of lunar samples- Microprobe studies of samples 12021 and 12022 - Viscosity of melts of selected lunar compositions
Lunar maria igneous rock compositions and magmatic liquid viscosity from samples 12021 and 12022, using microprobe analyses
Bottinga, Y.↗
Effects of viscosity and constraints on the dispersion and dissipation of waves in large blood vessels. II.
Comparison of previously described theoretical predictions with in vivo data from anesthetized dogs. It is shown that the observed attenuation of the pressure and axial waves cannot be accounted for by fluid viscosity alone. For large values of the frequency parameter alpha, the previous analysis is extended to include the effects of viscoelasticity of the vessel wall. The results indicate that the speeds of both types of waves are essentially unaffected by a realistic viscoelasticity model while the attenuation per wavelength is significantly increased and becomes frequency independent. There is fair agreement between theory and experiment.
Jones, E.↗
Turbulent-wake calculations with an eddy-viscosity model.
A simple eddy-viscosity model is shown to make it possible to calculate numerically the mean properties of a turbulent wake. Although the structure of the Reynolds stress terms is not resolved, the results obtained are adequate for predicting velocity profiles and displacement thicknesses.
Inouye, M.↗
Elastohydrodynamic analysis using a power law pressure-viscosity relation
An isothermal elastohydrodynamic (EHD) inlet analysis of the Grubin type which considers a power law pressure-viscosity relation and a finite pressure at the inlet edge of the Hertzian contact zone was performed. Comparisons made with published X-ray EHD film thickness data for a synthetic paraffinic oil and when conventional EHD theory showed that the present theory exhibits a slightly stronger film thickness load dependence than do previous isothermal EHD theories but far less than that exhibited by the measured data.
Loewenthal, S. H.↗
Calculation of eddy viscosity in a compressible turbulent boundary layer with mass injection and chemical reaction, volume 2
As described in Vol. 1, the eddy viscosity is calculated through the turbulent kinetic energy, in order to include the history of the flow and the effect of chemical reaction on boundary layer characteristics. Calculations can be performed for two different cooling concepts; that is, transpiration and regeneratively cooled wall cases. For the regenerative cooling option, coolant and gas side wall temperature and coolant bulk temperature in a rocket engine can be computed along the nozzle axis. Thus, this computer program is useful in designing coolant flow rate and cooling tube geometry, including the tube wall thickness as well as in predicting the effects of boundary layers along the gas side wall on thrust performances.
Omori, S.↗
Viscosity and thermal conductivity coefficients of gaseous and liquid oxygen
Equations and tables are presented for the viscosity and thermal conductivity coefficients of gaseous and liquid oxygen at temperatures between 80 K and 400 K for pressures up to 200 atm. and at temperatures between 80 K and 2000 K for the dilute gas. A description of the anomalous behavior of the thermal conductivity in the critical region is included. The tabulated coefficients are reliable to within about 15% except for a region in the immediate vicinity of the critical point. Some possibilities for future improvements of this reliability are discussed.
Hanley, H. J. M.↗
Calculation of eddy viscosity in a compressible turbulent boundary layer with mass injection and chemical reaction
The turbulent kinetic energy equation is coupled with boundary layer equations to solve the characteristics of compressible turbulent boundary layers with mass injection and combustion. The Reynolds stress is related to the turbulent kinetic energy using the Prandtl-Wieghardt formulation. When a lean mixture of hydrogen and nitrogen is injected through a porous plate into the subsonic turbulent boundary layer of air flow and ignited by external means, the turbulent kinetic energy increases twice as much as that of noncombusting flow with the same mass injection rate of nitrogen. The magnitudes of eddy viscosity between combusting and noncombusting flows with injection, however, are almost the same due to temperature effects, while the distributions are different. The velocity profiles are significantly affected by combustion. If pure hydrogen as a transpiration coolant is injected into a rocket nozzle boundary layer flow of combustion products, the temperature drops significantly across the boundary layer due to the high heat capacity of hydrogen. At a certain distance from the wall hydrogen reacts with the combustion products, liberating an extensive amount of heat.
Omori, S.↗
Pressure-viscosity measurements for several lubricants to 550 meganewtons per square meter /80,000 PSI/ and 149 C /300 F/
The viscosities of a number of liquid lubricants and lubricant formulations, determined as function of pressure, temperature, and shear stress by means of a high-pressure capillary viscometer, are reviewed. Where possible, these results are compared with those obtained by other techniques (optical elastohydrodynamics, oscillating crystal, and low shear capillary viscometry).
Jones, W. R., Jr.↗
Roll-up of aircraft trailing vortices using artificial viscosity
The artificial viscosity method of Kuwahara and Takami (1973) is used to calculate the roll-up of trailing vortices behind a number of practical aerodynamic configurations. Where possible, the results are compared for core location with available experimental data.
Bloom, A. M.↗
Viscosity and viscoelasticity of two-phase systems having diffuse interfaces
The equilibrium stability criterion for diffuse interfaces in a two-component solution with a miscibility gap requires that the interdiffusion flux vanish. If the system is continuously deformed, convective fluxes disrupt the equilibrium in the interface regions and induce a counter diffusive flux, which is dissipative and contributes to the apparent viscosity of the mixture. Chemical free energy is recoverably stored, causing viscoelastic phenomena. Both effects are significant.
Hopper, R. W.↗
Determining viscosities of liquids
Method requires only chemical composition and molecular structure to evaluate viscosity for many liquids. Accuracies of fifteen percent or better are obtained without experimentation.
Fedors, R. F.↗
Turbulent viscosity and Jupiter's tidal Q
A recent estimate of tidal dissipation by turbulent viscosity in Jupiter's convective interior predicts that the current value of the planet's tidal Q is roughly 5 million. We point out a fundamental error in this calculation, and show that turbulent dissipation alone implies that at present Q is about 50 trillion. Our reduced estimate for the rate of tidal dissipation shows conclusively that tidal torques have produced only negligible modifications of the orbits of the Galilean satellites over the age of the solar system.
Goldreich, P.↗
The effects of curvature and viscosity on baroclinic instability: A two-layer model
A linear stability analysis of a baroclinic zonal current contained between two parallel rigid boundaries is presented. Curvature is included by performing the analysis on a beta b-plane and viscosity by allowing for the effects of Ekman layers on the rigid boundaries. A two-layer model is used. This calculation was carried out to assist in the design of a spherical model of the general circulation of the earth's atmosphere for Spacelab. In the low-gravity environment on an orbiting vehicle, a dominant radial dielectric body force, analogous to planetary gravity, can be achieved over a volume of liquid held between two concentric spheres. The results show the Eady short wavelength cutoff, and long wavelength cutoffs due to Ekman damping and curvature.
Fowlis, W. W.↗
Moon-Mercury - Large impact structures, isostasy and average crustal viscosity
It is shown that Mercury's surface has only 70% as many large craters (of at least 200 km in diameter) as the moon. The density of Mercurian impact craters having diameters over 400 km is 30% of that of the moon, and for craters with diameters between 400 and 700 km, Mercurian density is 21% of that of the moon. The size-frequency distribution curve of Mercury is the same as the lunar cumulative -2 slope. The Mercurian curve, however, lies well below the 10% surface saturation level of the lunar curve. This may indicate that the old, heavily-cratered Mercurian terrain is not presently in a state of cratering equilibrium. The differences in crater and basin densities observed between Mercury and the moon may be functions of crater-production rates or of different crustal histories. The total isostatic compensation of impact craters having diameters of about 800 km suggests that the average viscosity of the Mercurian crust during approximately the past 4 eons was the same as that of the moon.
Schaber, G.↗