Shock-tube study of vibrational relaxation in nitrogen using pressure measurements
Vibrational relaxation behind incident shock waves in pure nitrogen, using end wall pressure measurements
Baganoff, D.↗
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Binary sequences with a relaxed Barker criterion
Binary sequences with relaxed Barker criterion, examining correlation coefficients
Seguin, G.↗
Effect of stress on electron relaxation times in n-type silicon
Stress effects on electron relaxation time anisotropies in n-type Si, using high temperature piezoresistivity model for population transfer rates
Littlejohn, M. A.↗
Shock-wave reflexion in a relaxing gas
Plane normal shock wave reflection in relaxing gas for shock tube endwall upstream and downstream dynamic pressures, using method of characteristics
Hanson, R. K.↗
Calculation of relaxing turbulent boundary layers downstream of tangential slot injection
Turbulent boundary layers calculation downstream of compressible relaxing slot injection flows, using finite difference method based on eddy viscosity model
Bushnell, D. M.↗
Numerical calculation of transonic flow about two-dimensional airfoils by relaxation procedures
Compressible transonic flow about two dimensional airfoils, developing inviscid nonlinear potential equations by relaxation procedures
Lomax, H.↗
Rotational relaxation in polar gases. III - Molecular dynamics
Exponential approximation of rotational relaxation of polar HCl and DCl at 300 and 500 K by molecular dynamics, comparing with perturbation calculations
Dugan, J. V., Jr.↗
Stress relaxation as a source of dimensional instability
Stress relaxation as source of dimensional instability in precision devices, discussing thermal cycling role in residual stress relief
Maringer, R. E.↗
Attenuation of seismic waves by grain boundary relaxation
Elastic seismic waves attenuation in polycrystalline ceramics and rocks by grain boundary relaxation, noting strong frequency dependence of earth mantle internal friction
Jackson, D. D.↗
Generalized relaxation methods applied to problems in transonic flow
Generalized relaxation methods application to transonic flow problems, combining with numerical integration theory for ordinary differential equations
Lomax, H.↗
Shock-tube study of vibrational relaxation in carbon monoxide using pressure measurements
Vibrational relaxation behind incident shock waves in CO based on shock tube pressure measurements at 2400-6000 K
Hanson, R. K.↗
Lunar glass. I - Densification and relaxation studies
Pressure histories from densification and relaxation measurements on lunar glass and synthetic samples, investigating refractive index changes after annealing
Faile, S. P.↗
Long-term aging of elastomers: Chemical stress relaxation of fluorosilicone rubber and other studies
Aerospace applications of elastomers are considered, including: propellant binders, bladder materials for liquid propellant expulsion systems, and fuel tank sealants for high-speed aircraft. A comprehensive molecular theory for mechanical properties of these materials has been developed but has only been tested experimentally in cases where chemical degradation processes are excluded. Hence, a study is being conducted to ascertain the nature, extent, and rate of chemical changes that take place in some elastomers of interest. Chemical changes that may take place in the fluorosilicone elastomer, LS 420, which is regarded as a fuel and high-temperature-resistant rubber are investigated. The kinetic analysis of the chemical stress relaxation and gel permeation chromatography studies comprise the major portion of the report.
Kalfayan, S. H.↗
A general relaxation method for inverse solution of the full radiative transfer equation.
The relaxation method for the inverse solution of the full radiative transfer equation is generalized to solve for all atmospheric parameters which appear in the integrand as functions or functionals, without any a priori information related to the expected solution. The method is illustrated by examples in the earth's atmosphere for the determination of water vapor mixing ratio profiles from observations in the 6.3-micron band.
Chahine, M. T.↗
Recent developments in the inversion by the method of relaxation
The relaxation method for inverse solution of the full radiative transfer equation is generalized to solve for all the atmospheric parameters that appear in the integrand as functions or functionals, without any a priori information about the expected solution. Illustrations are presented using the 7.5 micron CH4 band for determining temperature profiles in the Jovian atmosphere, and the 6.3 micron band for determining the water vapor mixing ratio in the earth's atmosphere.
Chahine, M. T.↗
Study of excitation transfer in a flowing helium afterglow pumped with a tuneable dye laser. II - Measurement of the rate coefficient for the rotational relaxation of He2/3p 3Pi-g/.
The results of the use of a fast-transient fluorescence technique in the examination of rotational relaxation caused by collisions with neutral helium atoms are discussed. Details regarding the production and detection of reacting species are considered, together with the analytical method used. A dye laser system with 4-methylcoumarin producing a pumping flux in the 4650 A region was employed in the investigations.
Collins, C. B.↗
Relaxation time measurements by an electronic method.
Description of a simple electronic system that permits the direct measurement of time constants of decaying signals. The system was used in connection with relaxation experiments on hydrogen and rubidium masers and was found to operate well. The use of a computing counter in the systems gives the possibility of making averages on several experiments and obtaining the standard deviation of the results from the mean. The program for the computing counter is given.
Brousseau, R.↗
Relaxation solutions for inviscid axisymmetric transonic flow over blunt or pointed bodies.
A finite-difference relaxation method is presented for numerical solution of the full potential equation and exact boundary conditions for general axisymmetric bodies is inviscid, steady transonic flow. Body-normal coordinates are used in the nose region and sheared cylindrical coordinates are used on the afterbody to accommodate corners such as boattails and flares. An improved difference scheme is used which does not require that the flow be nearly alined with a coordinate direction in supersonic regions, and which treats either subsonic or supersonic free streams. Numerical results are illustrated for some simple classical shapes such as spheres and ellipsoids, and for more practical shapes like tangent-ogives with boattails. Special attention is given to bodies which have been studied for area-rule applications. Agreement with available experimental results is good in cases where viscous effects and wind-tunnel wall interference are not important.
South, J. C., Jr.↗