92
92
Apr 7, 2010
04/10
by
Mark L. Gurari
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In the article it is carried out an operational analysis of a sound separator, selected optimal conditions of its operation and received simple expressions for determination of separation time at given coefficient of admixture concentration. Itâs proposed a direction of investigations for further efficiency increasing of the separators.
Topics: Acoustic separation, enrichment, continuity equation
Continuity equation for wave modeling is still being developed. There are quite a lot of versions of this equation. This research formulates continuity equation in a simple form to simplify its numerical and analytical solution. The formulation of the continuity equation is done by performing mass conservation law in a water column with free surface and by performing weighted total acceleration. Then, the continuity equation is performed along with the surface momentum equation and completed...
Topics: Continuity Equation, Weighted total acceleration equation.
202
202
Jun 21, 2010
06/10
by
Coates, K. D
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Design feasibility of auxiliary propulsion system for space shuttle
Topics: FLOW EQUATIONS, SEMIEMPIRICAL EQUATIONS, TRANSPORT PROPERTIES, TURBULENT FLOW, CONTINUITY EQUATION,...
249
249
Jul 26, 2010
07/10
by
Gertel, Maurice; Holland, Richar
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No Abstract Available
Topics: ALGORITHMS, LINEAR EQUATIONS, MATRICES (MATHEMATICS), MATRIX THEORY, VECTORS (MATHEMATICS),...
1,044
1.0K
May 29, 2011
05/11
by
Freeman, Jon C
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This short paper is in response to one that appeared in this journal a few years ago [2]. The article was a comment on a previous paper [1], which presented the transformation equations between the standard two-port parameters. The equations were stated to be valid for complex terminations; which are useful when S-parameters are treated. The authors in [2] made some incorrect conclusions concerning the concept of ''generalized scattering parameters'', and this paper seeks to clarify the...
Topics: VAPORS, SENSITIVITY, SUPERSATURATION, THERMAL DIFFUSION, CLOUD CHAMBERS, CONTINUITY EQUATION,...
2,032
2.0K
Jun 21, 2010
06/10
by
PRIDANTSEV, M. V
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STRUCTURE AND PROPERTIES OF HEAT-RESISTANT METALS AND ALLOY, STRENGTHENING OF STEELS AND ALLOYS, AND KINETICS AND MECHANICS OF OXIDATION
Topics: MATHEMATICAL MODELS, PERFORMANCE PREDICTION, SOLAR CELLS, COMPUTER PROGRAMS, CONTINUITY EQUATION,...
299
299
May 29, 2011
05/11
by
Murray, James E.; Tartabini, Paul V
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eye 299
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An entry, descent, and flight (EDF) trajectory profile for a Mars airplane mission is defined as consisting of the following elements: ballistic entry of an aeroshell; supersonic deployment of a decelerator parachute; subsonic release of a heat shield; release, unfolding, and orientation of an airplane to flight attitude; and execution of a pull up maneuver to achieve trimmed, horizontal flight. Using the Program to Optimize Simulated Trajectories (POST) a trajectory optimization problem was...
Topics: STATISTICAL ANALYSIS, SIMULATION, RELIABILITY ANALYSIS, METAL OXIDE SEMICONDUCTORS, THRESHOLD...
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255
Jul 26, 2010
07/10
by
Feyock, Stefa
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The problem of determining the behavior of physical systems subsequent to the occurrence of malfunctions is discussed. It is established that while it was reasonable to assume that the most important fault behavior modes of primitive components and simple subsystems could be known and predicted, interactions within composite systems reached levels of complexity that precluded the use of traditional rule-based expert system techniques. Reasoning from first principles, i.e., on the basis of...
Topics: COMPRESSIBLE FLOW, EQUATIONS OF MOTION, FLOW EQUATIONS, BERNOULLI THEOREM, CONTINUITY EQUATION,...
The results of an experimental study conducted to determine the geometric and radiometric effects of double resampling (bi-resampling) performed on image data in the process of performing map projection transformations are reported.
Topics: NASA Technical Reports Server (NTRS), IMAGE PROCESSING, IMAGERY, RADIO TELEMETRY, CONFORMAL...
A derivation of the continuum equations used for the analysis of turbulence is given. These equations include the continuity equation, the Navier-Stokes equations, and the heat transfer or energy equation. An experimental justification for using a continuum approach for the study of turbulence is given.
Topics: NASA Technical Reports Server (NTRS), CONTINUITY EQUATION, FLUID DYNAMICS, HEAT TRANSFER, TURBULENT...
An efficient implementation of the generalized method of cells micromechanics model is presented that allows analysis of periodic unidirectional composites characterized by repeating unit cells containing thousands of subcells. The original formulation, given in terms of Hill's strain concentration matrices that relate average subcell strains to the macroscopic strains, is reformulated in terms of the interfacial subcell tractions as the basic unknowns. This is accomplished by expressing the...
Topics: NASA Technical Reports Server (NTRS), MICROMECHANICS, MICROSTRUCTURE, STRESS DISTRIBUTION,...
The quasi-geostrophic omega-equation in flux form is developed as an example of a Poisson problem over a spherical shell. Solutions of this equation are obtained by applying a two-parameter Chebyshev solver in vector layout for CDC 200 series computers. The performance of this vectorized algorithm greatly exceeds the performance of its scalar analog. The algorithm generates solutions of the omega-equation which are compared with the omega fields calculated with the aid of the mass continuity...
Topics: NASA Technical Reports Server (NTRS), CHEBYSHEV APPROXIMATION, POISSON EQUATION, SPHERICAL SHELLS,...
146
146
May 23, 2011
05/11
by
Frank, L. A.; Sigwarth, J. B.; Craven, J. D.; Cravens, J. P.; Dolan, J. S.; Dvorsky, M. R.; Hardebeck, P. K.; Harvey, J. D.; Muller, D. W
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The Visible Imaging System (VIS) is a set of three low-light-level cameras to be flown on the POLAR spacecraft of the Global Geospace Science (GGS) program which is an element of the International Solar-Terrestrial Physics (ISTP) campaign. Two of these cameras share primary and some secondary optics and are designed to provide images of the nighttime auroral oval at visible wavelengths. A third camera is used to monitor the directions of the fields-of-view of these sensitive auroral cameras...
Topics: PLASMASPHERE, MAGNETIC STORMS, MAGNETIC FLUX, IONS, HYDRODYNAMICS, ELECTRONS, CONTINUITY EQUATION,...
The contribution of the graded region of implanted p-n junctions is analyzed using an exponential profile. Though previously neglected, it was recently shown that this contribution to the saturation current of HgCdTe diodes is significant. Assuming a dominant Auger recombination, an analytical solution to the continuity equation is obtained. An expression for the current generation by the graded region is presented for both ohmic and reflecting boundary conditions. A revised condition for a...
Topics: NASA Technical Reports Server (NTRS), IMPLANTATION, MERCURY CADMIUM TELLURIDES, P-N JUNCTIONS,...
We are interested in tracing the convective profiles of vertical Bridgman growth in two configurations, the pure Rayleigh convective mode and the combined Rayleigh-Marangoni mode. In order to do so, we conducted a numerical investigation that involved a finite volume calculation. The governing equations were integrated about a cell volume, using the Gauss Theorem and the volume variables like temperature and velocity were related to the surface variables. In order to solve for the pressure...
Topics: NASA Technical Reports Server (NTRS), BRIDGMAN METHOD, CRYSTAL GROWTH, MARANGONI CONVECTION,...
580
580
Jul 21, 2010
07/10
by
Crane, J. M.; Boucek, G. P., Jr.; Smith, W. D
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A flight management computer (FMC) control display unit (CDU) test was conducted to compare two types of input devices: a fixed legend (dedicated) keyboard and a programmable legend (multifunction) keyboard. The task used for comparison was operation of the flight management computer for the Boeing 737-300. The same tasks were performed by twelve pilots on the FMC control display unit configured with a programmable legend keyboard and with the currently used B737-300 dedicated keyboard. Flight...
Topics: ATMOSPHERIC CIRCULATION, SPATIAL RESOLUTION, VELOCITY, VERTICAL ORIENTATION, WINDS ALOFT,...
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182
Jul 26, 2010
07/10
by
Lamkin, Stephen L
texts
eye 182
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No Abstract Available
Topics: CONVERGENCE, CONTINUITY EQUATION, FLOW DISTRIBUTION, ITERATION, STOKES FLOW, DUCTED FLOW, FINITE...
203
203
May 22, 2011
05/11
by
NON
texts
eye 203
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A method for non-invasive evaluation of diaphragmatic function in humans measures the thickness of the diaphragm in real time with an ultrasonic device, and displays the variations of diaphragm thickness versus time. Formulae are given for calculating a quantitative value for the reserve fatigue capacity of a patient's diaphragm from data obtained by measuring the time limits for maintaining a constant breathing pattern on the display at two different pressure differentials in series with the...
Topics: CONSERVATION LAWS, CONTINUITY EQUATION, FLOW DISTRIBUTION, DIFFERENTIAL EQUATIONS, INTEGRAL...
A combination of experimental and modeling work is summarized in two areas: first, the calculation of excess free carrier and space charge distributions near contacts and their effects on device resistivity, and second, the characterization of a slow transient response (tau approx. 1 sec) in Ge:Be detectors which is due to trapping associated with Be(+) formation. In both cases, analytical models, based on continuity and rate equations, have been developed to enable the application of these...
Topics: NASA Technical Reports Server (NTRS), CHARGE DISTRIBUTION, ELECTRICAL RESISTIVITY, MATHEMATICAL...
A 3D 'atomistic' simulation technique to study random impurity induced threshold voltage lowering and fluctuations in sub 0. 1 micron MOSFETs is presented. It allows statistical analysis of random impurity effects down to the individual impurity level-Efficient algorithms based on a single solution of Poisson's equation, followed by the solution of a simplified current continuity equation are used in the simulations.
Topics: NASA Technical Reports Server (NTRS), STATISTICAL ANALYSIS, RELIABILITY ANALYSIS, METAL OXIDE...
An analysis of the oscillatory fluid flow in the vicinity of a circular orifice with a steady grazing flow is presented. The study is similar to that of Hersh and Rogers but with the addition of the grazing flow. Starting from the momentum and continuity equations, a considerably simplified system of partial differential equations is developed with the assumption that the flow can be described by an oscillatory motion superimposed upon the known steady flow. The equations are seen to be linear...
Topics: NASA Technical Reports Server (NTRS), ACOUSTIC IMPEDANCE, FLUID FLOW, GRAZING FLOW, ORIFICES,...
The Finite Element Semiconductor Three-dimensional Analyzer by Ralph O. Clark (FIESTA ROC) is a computational tool for investigating in detail the performance of arbitrary solar cell structures. As its name indicates, it uses the finite element technique to solve the fundamental semiconductor equations in the cell. It may be used for predicting the performance (thereby dictating the design parameters) of a proposed cell or for investigating the limiting factors in an established design.
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, FINITE ELEMENT METHOD, PERFORMANCE...
Via the hydrodynamical formulation of quantum mechanics, an approach to the problem of tunneling through sharp-edged potential barriers is developed. Above all, it is shown how more general boundary conditions follow from the continuity of mass, momentum, and energy.
Topics: NASA Technical Reports Server (NTRS), BOUNDARY CONDITIONS, CONTINUITY EQUATION, HYDRODYNAMIC...
173
173
May 23, 2011
05/11
by
Stephens, K. M.; Bauer, S. H
texts
eye 173
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The primary objective of this study was to ascertain whether low molecular weight hydrocarbons (LMWH) in the range C4 to C7, upon heating to temperatures above 900 K, emit IR radiations at frequencies that correspond to the 'unidentified infrared' (UIR) features - the recorded emissions from a variety of astronomical sources - reflection nebulae, HII regions, planetary nebulae, spiral galaxies and other extra galactic objects. We describe IR emission spectra recorded from shock-heated gases...
Topics: STAR FORMATION, ISOTHERMAL PROCESSES, DENSITY DISTRIBUTION, GAS DENSITY, CONTINUITY EQUATION, MASS...
A finite element method for the computation of the transonic flow with shocks past airfoils is presented using the artificial viscosity concept for the local supersonic regime. Generally, the classic element types do not meet the accuracy requirements of advanced numerical aerodynamics requiring special attention to the choice of an appropriate element. A series of computed pressure distributions exhibits the usefulness of the method.
Topics: NASA Technical Reports Server (NTRS), AIRFOILS, CONTINUITY EQUATION, FAR FIELDS, FINITE ELEMENT...
An analysis is presented to calculate damping in ring seals for a compressible fluid. Results show that damping in tapered ring seals (optimized for stiffness) is less than that in straight bore ring seals for the same minimum clearance. Damping in ring seals can promote fractional frequency whirl and can, thus, be detrimental. Thus, tapered seals can benefit rotor and seal stability by having lower damping as well as higher stiffness. Use of incompressible results leads to large errors.
Topics: NASA Technical Reports Server (NTRS), COMPRESSIBLE FLUIDS, DAMPING, O RING SEALS, ROTARY STABILITY,...
There has been, recently, a revival of the stability problem of accretion disks. Much of this renewed interest is due to recent observational data on transient soft X-ray novae, which are low-mass X-ray binaries. It is widely believed that nonsteady mass transfer from the secondary onto the compact primary, through an accretion disk, is the reason for the observed spectacular events in the form of often repetitive outbursts, with recurrence times ranging from 1 to 60 yr and duration time on the...
Topics: NASA Technical Reports Server (NTRS), ACCRETION DISKS, CONSERVATION EQUATIONS, LUMINOSITY, MASS...
A unified theory is described of design sensitivity analysis of linear and nonlinear structures for shape, nonshape and material selection problems. The concepts of reference volume and adjoint structure are used to develop the unified viewpoint. A general formula for design sensitivity analysis is derived. Simple analytical linear and nonlinear examples are used to interpret various terms of the formula and demonstrate its use.
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT DESIGN, AIRCRAFT STRUCTURES, CONTINUUM MECHANICS,...
A unified approach for solving incompressible flows has been investigated in this study. The numerical CTVD (Centered Total Variation Diminishing) scheme used in this study was successfully developed by Sanders and Li for compressible flows, especially for the high speed. The CTVD scheme possesses better mathematical properties to damp out the spurious oscillations while providing high-order accuracy for high speed flows. It leads us to believe that the CTVD scheme can equally well apply to...
Topics: NASA Technical Reports Server (NTRS), ALTERNATING DIRECTION IMPLICIT METHODS, COMPUTATIONAL FLUID...
872
872
Jul 25, 2010
07/10
by
Huh, Oscar Karl; Leibowitz, Scott G.; Dirosa, Donald; Hill, John M
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The use of NOAA Advanced Very High Resolution Radar/High Resolution Picture Transmission (AVHRR/HRPT) imagery for earth resource applications is provided for the applications scientist for use within the various Earth science, resource, and agricultural disciplines. A guide to processing NOAA AVHRR data using the hardware and software systems integrated for this NASA project is provided. The processing steps from raw data on computer compatible tapes (1B data format) through usable qualitative...
Topics: COMPUTATIONAL FLUID DYNAMICS, MOMENTUM THEORY, NAVIER-STOKES EQUATION, NUSSELT NUMBER, HEAT...
This report discusses the uncertainty analysis performed in support of a new test analysis and performance prediction model for the Space Shuttle Main Engine. The new model utilizes uncertainty estimates for experimental data and for the analytical model to obtain the most plausible operating condition for the engine system. This report discusses the development of the data sets and uncertainty estimates to be used in the development of the new model. It also presents the application of...
Topics: NASA Technical Reports Server (NTRS), SPACE SHUTTLE MAIN ENGINE, PERFORMANCE PREDICTION,...
Finite difference equations are derived for sound propagation in a two dimensional, straight, soft wall duct with a uniform flow by using the wave envelope concept. This concept reduces the required number of finite difference grid points by one to two orders of magnitude depending on the length of the duct and the frequency of the sound. The governing acoustic difference equations in complex notation are derived. An exit condition is developed that allows a duct of finite length to simulate...
Topics: NASA Technical Reports Server (NTRS), ACOUSTIC DUCTS, FINITE DIFFERENCE THEORY, SOUND PROPAGATION,...
341
341
May 23, 2011
05/11
by
Fennell, J. F
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This document summarizes the results of mission definition studies for solar electric propulsion missions that have been carried out over the last approximately three years. The major output from the studies has been two proposals which were submitted to NASA in response to Announcements of Opportunity for missions and an ongoing Global Magnetospheric Dynamics mission study. The bulk of this report consists of copies of the proposals and preliminary materials from the GMD study that will be...
Topics: NAVIER-STOKES EQUATION, PARTIAL DIFFERENTIAL EQUATIONS, LAGRANGIAN FUNCTION, ENERGY TRANSFER, EULER...
We present a multigrid solver for the exponential fitting method. The solver is applied to the current continuity equations of semiconductor device simulation in two dimensions. The exponential fitting method is based on a mixed finite element discretization using the lowest-order Raviart-Thomas triangular element. This discretization method yields a good approximation of front layers and guarantees current conservation. The corresponding stiffness matrix is an M-matrix. 'Standard' multigrid...
Topics: NASA Technical Reports Server (NTRS), CONTINUITY EQUATION, ELECTRIC CURRENT, FINITE ELEMENT METHOD,...
1,134
1.1K
Sep 20, 2010
09/10
by
NON
texts
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Given here are the proceedings of the 3rd Space Exploration Initiative (SEI) Technical Interchange. Topics covered include the First Lunar Outpost (FLO), the Lunar Resource Mapper, lunar rovers, lunar habitat concepts, lunar shelter construction analysis, thermoelectric nuclear power systems for SEI, cryogenic storage, a space network for lunar communications, the moon as a solar power satellite, and off-the-shelf avionics for future SEI missions.
Topics: CONVECTION, BOUNDARY CONDITIONS, CAVITIES, CONTINUITY EQUATION, GAUSSIAN ELIMINATION, MOMENTUM,...
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207
Jul 25, 2010
07/10
by
Stanbery, Billy J
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Multijunction thin film solar cells utilizing GaAs and CuInSe2 as semiconductor absorbers are rapidly developing, becoming a viable technology for space power systems with an unparalleled combination of high efficiency, low mass, and high radiation tolerance. The prospect for evolutionary improvement of this type of cell towards efficiency of approximately equals 30 percent and specific power greater than 1 kW/kg while retaining the attribute of high radiation tolerance are good. Limitations of...
Topics: BOUNDARY LAYER EQUATIONS, SWIRLING, SYMMETRY, THREE DIMENSIONAL BOUNDARY LAYER, VORTICES, BOUNDARY...
The aim of the present research program is the development of more efficient and reliable calculation schemes for the coupled momentum and continuity equations. The resulting schemes would significantly reduce the expense of computing complex flows such as those in combustion chambers, gas turbines, and heat exchangers.
Topics: NASA Technical Reports Server (NTRS), CONTINUITY EQUATION, FLUID DYNAMICS, MOMENTUM, NEWTON-RAPHSON...
A simple analytical microburst model was developed for use in estimating vertical winds from horizontal wind measurements. It is an axisymmetric, steady state model that uses shaping functions to satisfy the mass continuity equation and simulate boundary layer effects. The model is defined through four model variables: the radius and altitude of the maximum horizontal wind, a shaping function variable, and a scale factor. The model closely agrees with a high fidelity analytical model and...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT SAFETY, BOUNDARY LAYERS, MATHEMATICAL MODELS,...
198
198
May 23, 2011
05/11
by
Veiga, Robert E.; Cunnold, Derek M.; Chu, William P.; McCormick, M. Patric
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Ozone profiles measured by the Stratospheric Aerosol and Gas Experiments (SAGE) 1 and 2 are compared with ozonesonde profiles at 24 stations over the period extending from 1979 through 1991. Ozonesonde/satellite differences at 21 stations with SAGE 2 overpasses were computed down to 11.5 km in midlatitudes, to 15.5 km in the lower latitudes, and for nine stations with SAGE 1 overpasses down to 15.5 km. The set of individual satellite and ozonesonde profile comparisons most closely colocated in...
Topics: LIQUID FLOW, CONTINUITY EQUATION, LINEAR SYSTEMS, CROSS SECTIONS, GRAVITATIONAL EFFECTS, AIR WATER...
A simple control volume model has been developed to calculate the discharge coefficient through a mass flow plug (MFP) and validated with a calibration experiment. The maximum error of the model in the operating region of the MFP is 0.54%. The model uses the MFP geometry and operating pressure and temperature to couple continuity, momentum, energy, an equation of state, and wall shear. Effects of boundary layer growth and the reduction in cross-sectional flow area are calculated using an in-...
Topics: NASA Technical Reports Server (NTRS), CALIBRATING, PRESSURE EFFECTS, COMPUTATIONAL FLUID DYNAMICS,...
Preliminary results are presented of an investigation into the development of a procedure to provide curvature continuity between biparametric cubic Bezier surface patches in the computer-aided design package known as SMART (Solid Modeling Aerospace Research Tools). This initial effort was aimed at providing the designer with the ability to locally impose curvature continuity at the intersection of two Bezier curves without disrupting either the curvature or slope continuity that may exist at...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE SYSTEMS, COMPUTER AIDED DESIGN, COMPUTER PROGRAMS,...
166
166
Jun 21, 2010
06/10
by
Payne, P
texts
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Effect of sintering TiAg contact on p/n cells from effect of heat treatment on lithium diffused cells
Topics: GAS FLOW, CONTINUITY EQUATION, EQUATIONS OF STATE, GAS DYNAMICS, INDEPENDENT VARIABLES, NOZZLE...
The equations of momentum annd continuity are combined and linearized yielding the one dimensional nonhomogeneous acoustic wave equation. Three terms in the non-homogeneous equation act as acoustic sources and are taken to be forcing functions acting on the homogeneous wave equation. The three source terms are: fluctuating entropy, turbulence gradients, and turbulence-flame interactions. Each source term is discussed. The turbulence-flame interaction source is used as the basis for computing...
Topics: NASA Technical Reports Server (NTRS), AEROACOUSTICS, COMBUSTION STABILITY, FLAMES, NOISE...
A new technique was developed for the solution of the incompressible Navier-Stokes equations. The numerical technique, derived from a pressure substitution method (PSM), overcomes many of the deficiencies of the pressure correction method. This technique allows for the direct solution of the actual pressure in the form of a Poisson equation which is derived from the pressure weighted substitution of the full momentum equations into the continuity equation. Two dimensional internal flows are...
Topics: NASA Technical Reports Server (NTRS), CONTINUITY EQUATION, CORRECTION, INCOMPRESSIBLE FLOW,...
This paper examines uniqueness and stability results for an inverse problem in thermal imaging. The goal is to identify an unknown boundary of an object by applying a heat flux and measuring the induced temperature on the boundary of the sample. The problem is studied both in the case in which one has data at every point on the boundary of the region and the case in which only finitely many measurements are available. An inversion procedure is developed and used to study the stability of the...
Topics: NASA Technical Reports Server (NTRS), EDGE DETECTION, INTEGRAL EQUATIONS, INVERSIONS, LINEAR...
An existing computer code that determines the flow path for an axial-flow compressor either for a given number of stages or for a given overall pressure ratio was modified for use in air-breathing engine conceptual design studies. This code uses a rapid approximate design methodology that is based on isentropic simple radial equilibrium. Calculations are performed at constant-span-fraction locations from tip to hub. Energy addition per stage is controlled by specifying the maximum allowable...
Topics: NASA Technical Reports Server (NTRS), AIR BREATHING ENGINES, COMPUTER PROGRAMS, DESIGN ANALYSIS,...
The three-dimensional, time-dependent primitive equations of motion were numerically integrated for the case of turbulent channel flow. A partially implicit numerical method was developed. An important feature of this scheme is that the equation of continuity is solved directly. The residual field motions were simulated through an eddy viscosity model, while the large-scale field was obtained directly from the solution of the governing equations. An important portion of the initial velocity...
Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, EDDY VISCOSITY, INCOMPRESSIBLE FLOW,...
A review of the equations used to determine the 1-D vapor transport in the thermal diffusion cloud chamber (TDCC) is presented. These equations closely follow those of the classical Stefan tube problem in which there is transport of a volatile species through a noncondensible, carrier gas. In both cases, the very plausible assumption is made that the background gas is stagnant. Unfortunately, this assumption results in a convective flux which is inconsistent with the momentum and continuity...
Topics: NASA Technical Reports Server (NTRS), VAPORS, THERMAL DIFFUSION, CLOUD CHAMBERS, CONTINUITY...
This report documents the development of a two dimensional finite element based numerical model for efficient characterization of the Hall thruster plasma dynamics in the framework of multi-fluid model. Effect of the ionization and the recombination has been included in the present model. Based on the experimental data, a third order polynomial in electron temperature is used to calculate the ionization rate. The neutral dynamics is included only through the neutral continuity equation in the...
Topics: NASA Technical Reports Server (NTRS), MATHEMATICAL MODELS, NUMERICAL ANALYSIS, ELECTRON ENERGY,...
A revised version of Dodge's split-velocity method for numerical calculation of compressible duct flow was developed. The revision incorporates balancing of mass flow rates on each marching step in order to maintain front-to-back continuity during the calculation. The (checkerboard) zebra algorithm is applied to solution of the three dimensional continuity equation in conservative form. A second-order A-stable linear multistep method is employed in effecting a marching solution of the...
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, COMPRESSIBLE FLOW, DUCTED FLOW, NAVIER-STOKES...
