Hguides with artificial and laminated dielectric slabs
H-guide dielectric losses reduction by use of artificial and laminated dielectric slabs
Tischer, F. J.↗
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Microwave properties of slabs of uniformly magnetized material filling the cross section of a rectangular waveguide operating in TE sub NO modes
Microwave properties of uniformly magnetized slabs filling cross section of rectangular lossless waveguide operating in specific modes
Obrien, K. C.↗
Bondline temperature of a two-layer slab subjected to aeroheating - Graphical solution
Two-layer slab under aeroheating, solving bondline temperature graphically
Harris, H. J.↗
Electromagnetic wave propagation in a lossy plasma slab with a gradient transverse to the incident wave
Computer solution of plane electromagnetic wave interaction with bounded inhomogeneous plasma slab with electron density gradient transverse to wave
Gal, G.↗
Solution of an initial-value problem in linear transport theory - Monoenergetic neutrons in a slab with infinite reflectors
Solution of initial value problem in linear transport theory obtained by monoenergetic neutrons migrating in thin slab with infinite reflector and isotropic scattering
Bowden, R. L.↗
Kinetic theory of electromagnetic waves obliquely incident upon a plasma slab
Kinetic theory of electromagnetic waves obliquely incident upon plasma slab considered as boundary value problem
Crownfield, F. R., Jr.↗
A nonhomogeneous boundary-value problem for the linear transport equation for a slab geometry
Finite thickness infinite slab with radiation from time dependent source, solving nonhomogeneous boundary value problem for linear transport equation
Hintz, G. R.↗
Flow field predictions for a slab delta wing at incidence
Theoretical results are presented for the structure of the hypersonic flow field of a blunt slab delta wing at moderately high angle of attack. Special attention is devoted to the interaction between the boundary layer and the inviscid entropy layer. The results are compared with experimental data. The three-dimensional inviscid flow is computed numerically by a marching finite difference method. Attention is concentrated on the windward side of the delta wing, where detailed comparisons are made with the data for shock shape and surface pressure distributions. Surface streamlines are generated, and used in the boundary layer analysis. The three-dimensional laminar boundary layer is computed numerically using a specially-developed technique based on small cross-flow in streamline coordinates. In the rear sections of the wing the boundary layer decreases drastically in the spanwise direction, so that it is still submerged in the entropy layer at the centerline, but surpasses it near the leading edge. Predicted heat transfer distributions are compared with experimental data.
Conti, R. J.↗
Electron emission produced by photointeractions in a slab target
The current density and energy spectrum of escaping electrons generated in a uniform plane slab target which is being irradiated by the gamma flux field of a nuclear reactor are calculated by using experimental gamma energy transfer coefficients, electron range and energy relations, and escape probability computations. The probability of escape and the average path length of escaping electrons are derived for an isotropic distribution of monoenergetic photons. The method of estimating the flux and energy distribution of electrons emerging from the surface is outlined, and a sample calculation is made for a 0.33-cm-thick tungsten target located next to the core of a nuclear reactor. The results are to be used as a guide in electron beam synthesis of reactor experiments.
Thinger, B. E.↗
Propagation through a slab of irregularities in a magneto-ionic medium.
A theory is developed to describe the propagation of characteristic waves through an infinite slab of irregularities in a magneto-ionic medium. The theory makes use of the asymptotic Green's dyadic. The results show that mode conversion is possible through scattering from irregularities in an anisotropic background. Some special cases are discussed and an example is given.
Simonich, D. M.↗
TM surface wave diffraction by a truncated dielectric slab recessed in a perfectly conducting surface
The diffraction of a TM sub o surface wave by a terminated dielectric slab which is flush mounted in a perfectly conducting surface is studied. The incident surface wave gives rise to waves reflected and diffracted by the termination; these reflected and diffracted fields may be expressed in terms of the geometrical theory of diffraction by introducing surface wave reflection and diffraction coefficients which are associated with the termination. In this investigation, the surface wave reflection and diffraction coefficients have been deduced from a formally exact solution to this canonical problem. The solution is obtained by a combination of the generalized scattering matrix technique and function theoretic methods.
Pathak, P. H.↗
Sound-absorbing slabs and structures based on granular materials (bound and unbound)
Sound absorbing slabs and structures made up of bound or unbound granular materials are considered and how to manufacture these elements at the building site. The raw material is a single grain powder (sand, expanded blast furnace slag, etc.) that imparts to the end products an apparent porosity of 25-45% and an energy dissipation within the structure leading to absorption coefficients that can be compared with those of mineral wool and urethane.
Petre-Lazar, S.↗
Transients in a periodic slab - Coupled waves approach
The reflection and transmission of rectangular and Gaussian pulses impinging on a periodically stratified slab are studied and a number of examples are illustrated and analyzed. The coupled waves approach is used to derive the reflection and transmission coefficient, then the fast Fourier transform is used to illustrate the transient responses.
Elachi, C.↗
Angular sensitivities of scintillator slab configurations for location of gamma ray bursts
Thin flat scintillator slabs are a useful means of measuring the angular location of gamma ray fluxes of astronomical interest. A statistical estimate of position error was made of two scintillator systems suitable for gamma ray burst location from a balloon or satellite platform. A single rotating scintillator with associated flux monitor is compared with a pair of stationary orthogonal scintillators. Position error for a strong burst is of the order of a few arcmin if systematic errors are ignored.
Gregory, J. C.↗
Radiation from the open end of a cylindrical or conical pipe and scattering from the end of a rod or slab
The radiation of sound through the open end of a cylindrical or conical pipe of any cross section, or through a hole in a plane wall, is analyzed theoretically. The scattering of a sound wave by the end of a rod or slab is also treated. Only the case in which the wavelength is large compared with a typical radial dimension of the opening or of the end is considered. The method of matched asymptotic expansions is employed. Results on end corrections and reflection coefficients previously obtained by Helmholtz (1860), Rayleigh (1945), and Bazer and Karp (1954), using intuitive arguments, are recovered and verified. Agreement is found with the exact results of Levine and Schwinger (1948) and Vainstein (1948), as well as with the small radial-dimension/wavelength results of Lesser and Lewis (1972), in the cases they treated. In addition various new results are obtained.
Ting, L.↗
A slab model for computing ground temperature in climate models
A method is developed for computing the ground temperature accurately over both the diurnal and annual cycles. The ground is divided vertically into only two or three slabs, resulting in very efficient computation. Seasonal storage and release of heat is incorporated, and thus the method is well suited for use in climate models.
Lebedeff, S.↗
Wave propagation through a random medium - The random slab problem
The first-order smoothing approximation yields integral equations for the mean and the two-point correlation function of a wave in a random medium. A method is presented for the approximate solution of these equations that combines features of the eiconal approximation and of the Born expansion. This method is applied to the problem of reflection and transmission of a plane wave by a slab of a random medium. Both the mean wave and the covariance are calculated to determine the reflected and transmitted amplitudes and intensities.
Acquista, C.↗
Analysis of solidification interface shape during continuous casting of a slab
An analysis was made of the two-dimensional interface shape of a slab ingot being cast continuously by withdrawing it from a mold. The sides of the ingot are being cooled and the upper boundary of the ingot is in contact with a pool of molten metal. The solidification interface shape was determined from the analysis of the heat flow, utilizing the condition that the solidification interface is at constant temperature and must be normal to the lines of heat flow carrying away latent heat of fusion from the interface. The analysis includes the effect of interface curvature which, for a constant rate of withdrawing the cast ingot from the mold, causes the solidification to be nonuniform along the interface. The analysis was carried out by a conformal mapping procedure.
Siegel, R.↗