475
475
Jul 26, 2010
07/10
by
Rey, Charles A
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The development of high temperature containerless processing equipment and the design and evaluation of associated systems required for microgravity materials processing and property measurements are discussed. Efforts were directed towards the following task areas: design and development of a High Temperature Acoustic Levitator (HAL) for containerless processing and property measurements at high temperatures; testing of the HAL module to establish this technology for use as a positioning...
Topics: AERODYNAMIC HEAT TRANSFER, RECIRCULATIVE FLUID FLOW, SIMULATION, BRUSHES, CONVECTIVE HEAT TRANSFER,...
A peristaltic pump is disclosed which includes a roller assembly on which is mounted a series of pump rollers. As the roller assembly is rotated by a drive gear the pump rollers are driven in reverse rotation by means of a stationary ring gear and pump roller gears. An upper pressure shoe plate and a lower pressure shoe plate are positioned above sets of flexible tubing. The tubing is sandwiched between the pressure shoe plates and the pump rollers. A highly compact pump is provided having...
Topics: NASA Technical Reports Server (NTRS), MECHANICAL DRIVES, PUMPS, REMOTE CONTROL, LINKAGES,...
263
263
Jul 26, 2010
07/10
by
Vaughan, Victor L., Jr
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No Abstract Available
Topics: ADDITIVES, HYDROGEN, PROPANE, RECIRCULATIVE FLUID FLOW, SHEAR LAYERS, BLUFF BODIES, FLAME HOLDERS,...
Turbulent swirling flow, the STARPIC computer code, turbulence modeling of turbulent flows, the k-xi turbulence model and extensions, turbulence parameters deduction from swirling confined flow measurements, extension of the k-xi to confined swirling recirculating flows, and general predictions for confined turbulent swirling flow are discussed.
Topics: NASA Technical Reports Server (NTRS), RECIRCULATIVE FLUID FLOW, SWIRLING, TURBULENT FLOW, COMPUTER...
226
226
May 23, 2011
05/11
by
Chestney, Louis S.; Sicker, Ronald J
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This report describes the results of in orbit calibration data collected for a Space Acceleration Measurement System (SAMS) Triaxial Sensor Head (TS H) and the methods used to process the data for bias and gravity levels.
Topics: FLOW DISTRIBUTION, FREE FLOW, SYMMETRY, NAVIER-STOKES EQUATION, NOZZLE GEOMETRY, PRESSURE...
The progress report on heterogeneous photocatalytic oxidation of atmospheric trace contaminants covering the period from 1 May - 31 Oct. 1992 is presented. The two topics discussed are photoreactor monolith fundamental studies and monolith reactor operation: batch recirculation system. Concentration profiles are shown.
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC COMPOSITION, EXHAUST EMISSION, MATHEMATICAL...
1,228
1.2K
Jul 12, 2010
07/10
by
Nunn, H. T
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An exemption from certain FAA regulations which stereotype simulator flight training was obtained and pilots with current line experience were used to prepare and develop scenarios for a program in which each crew member would be trained to recognize and properly use all available resouces. The development of the scenarios for training to proficiency and pilot reaction to the training sessions are discussed.
Topics: AIRCRAFT FUEL SYSTEMS, VISCOUS FLOW, AIRCRAFT FUELS, HEATING EQUIPMENT, JET ENGINE FUELS, LOW...
A model is suggested in which some of the important features of the circulating flow inside the two-dimensional near wake are derived by assuming a slow viscous flow. The theory considers the flow away from the body base. It is found that there is a region of constant speed merging, as we go downstream, into a region of stagnation-apex flow. The velocity returning from the rear stagnation point along the center streamline is shown to be a slowly varying function of the 'wedge-angle,' of the...
Topics: NASA Technical Reports Server (NTRS), RECIRCULATIVE FLUID FLOW, STAGNATION POINT, WAKES, BOUNDARY...
The hybrid-upwind finite difference schemes employed in generally available combustor codes possess excessive numerical diffusion errors which preclude accurate quantative calculations. The present study has as its primary objective the identification and assessment of an improved solution algorithm as well as discretization schemes applicable to analysis of turbulent viscous recirculating flows. The assessment is carried out primarily in two dimensional/axisymetric geometries with a view to...
Topics: NASA Technical Reports Server (NTRS), COMBUSTION, FINITE DIFFERENCE THEORY, RECIRCULATIVE FLUID...
A bulk energy storage system is designed with an electrically rechargeable reduction-oxidation (REDOX) cell divided into two compartments by a membrane, each compartment containing an electrode. An anode fluid is directed through the first compartment at the same time that a cathode fluid is directed through the second compartment. Means are provided for circulating the anode and cathode fluids, and the electrodes are connected to an intermittent or non-continuous electrical source, which when...
Topics: NASA Technical Reports Server (NTRS), CELL ANODES, ELECTRIC ENERGY STORAGE, STORAGE BATTERIES, CELL...
The effort to design, fabricate, and test a flight prototype Filter Regeneration Unit used to regenerate (clean) fluid particulate filter elements is reported. The design of the filter regeneration unit and the results of tests performed in both one-gravity and zero-gravity are discussed. The filter regeneration unit uses a backflush/jet impingement method of regenerating fluid filter elements that is highly efficient. A vortex particle separator and particle trap were designed for zero-gravity...
Topics: NASA Technical Reports Server (NTRS), FLUID FILTERS, HYDRAULIC EQUIPMENT, RECIRCULATIVE FLUID FLOW,...
The characteristics of the recirculation zones in confined coaxial turbulent jets are investigated numerically employing the kappa - epsilon turbulence model. The geometrical arrangement corresponds to the experimental study of Owen (AIAA J. 1976) and the investigation is undertaken to provide information for isothermal flow relevant to combustor flows. For the first time, the shape, size, and location of the recirculation zones for the above experimental configuration are correctly predicted....
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, ISOTHERMAL FLOW, PREDICTIONS,...
Progress in implementing and refining two near-wall turbulence models in which the near-wall region is divided into either two or three zones is outlined. These models were successfully applied to the computation of recirculating flows. The research was further extended to obtaining experimental results of two different recirculating flow conditions in order to check the validity of the present models. Two different experimental apparatuses were set up: axisymmetric turbulent impinging jets on...
Topics: NASA Technical Reports Server (NTRS), DYNAMIC MODELS, RECIRCULATIVE FLUID FLOW, TURBULENCE MODELS,...
The time dependent Navier-Stokes equations in mass averaged variables are solved for transonic flow over axisymmetric boattail plume simulator configurations. Numerical solution of these equations is accomplished with the unsplit explict finite difference algorithm of MacCormack. A grid subcycling procedure and computer code vectorization are used to improve computational efficiency. The two layer algebraic turbulence models of Cebeci-Smith and Baldwin-Lomax are employed for investigating...
Topics: NASA Technical Reports Server (NTRS), BOATTAILS, FINITE DIFFERENCE THEORY, NAVIER-STOKES EQUATION,...
This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet CELSS tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and...
Topics: NASA Technical Reports Server (NTRS), HYDROPONICS, MICROORGANISMS, CLOSED ECOLOGICAL SYSTEMS,...
Turbulence modeling approaches were examined from the standpoint of their capability to predict the complex flowfield features observed in scramjet combustions. Thus, for example, the accuracy of each turbulence model, with respect to the prediction of recirculating flows, was examined. It was observed that for large diameter ratio axisymmetric sudden expansion flows, a choice of turbulence model was not critical because of the domination of their flowfields by pressure forces. For low diameter...
Topics: NASA Technical Reports Server (NTRS), FLOW DISTRIBUTION, SUPERSONIC COMBUSTION RAMJET ENGINES,...
This viewgraph presentation discusses joint velocity-scalar PDF method; turbulent combustion modeling issues for gas turbine combustors; PDF calculations for a recirculating flow; stochastic dissipation model; joint PDF calculations for swirling flows; spray calculations; reduced kinetics/manifold methods; parallel processing; and joint PDF focus areas.
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHEMISTRY, PROBABILITY DENSITY FUNCTIONS,...
The development and evaluation of a liquid/gas vortex type separator design eliminating liquid and semi-liquid (suds) carryover into air recirculating system were described. Consideration was given to a number of soaps other than the "Miranol JEM" which was the low sudsing soap used in previous test runs of the space shower. Analysis of test parameters and prototype testing resulted in a revised separator configuration and a better understanding of the suds generating mechanism in the...
Topics: NASA Technical Reports Server (NTRS), GASES, HUMAN BODY, HYGIENE, ROTATING LIQUIDS, SEPARATORS,...
Scrubbers required to reduce N2O4 contamination of nitrogen vent gas streams to a safe level to preclude health hazard to personnel and to preclude adverse environmental effects were developed. The scrubber principle involved is to absorb and neutralize the N2O4 component in a closed circuit circulating water/chemical solution in a vertical counter-flow, packed-tower configuration. The operational and performance test requirements for the scrubbers consist of demonstrating that the exit gas...
Topics: NASA Technical Reports Server (NTRS), LIQUID ROCKET PROPELLANTS, NITROGEN TETROXIDE, RECIRCULATIVE...
An opposed reacting jet combustor (ORJ) was tested at a pressure of 1 atmosphere. A premixed propane/air stream was stabilized by a counterflowing jet of the same reactants. The resulting intensely mixed zone of partially reacted combustion products produced stable combustion at equivalence ratios as low as 0.45. Measurements are presented for main stream velocities of 7.74 and 13.6 m/sec with an opposed jet velocity of 96 m/sec, inlet air temperatures from 300 to 600 K, and equivalence ratios...
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, FUEL CONTAMINATION, JET THRUST,...
561
561
May 23, 2011
05/11
by
Santoro, Robert J
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A series of uni-element rocket injector studies were completed to provide benchmark quality data needed to validate computational fluid dynamic models. A shear coaxial injector geometry was selected as the primary injector for study using gaseous hydrogen/oxygen and gaseous hydrogen/liquid oxygen propellants. Emphasis was placed on the use of nonintrusive diagnostic techniques to characterize the flowfields inside an optically-accessible rocket chamber. Measurements of the velocity and species...
Topics: REYNOLDS STRESS, CUBIC EQUATIONS, ROTATING FLUIDS, STRESS ANALYSIS, AIRCRAFT ENGINES, TURBULENT...
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...
Combustor design phenomena; recirculating flows research; single-wire, six-orientation, eddy dissipation rate, and turbulence modeling measurement; directional sensitivity (DS); calibration equipment, confined jet facility, and hot-wire instrumentation; effects of swirl, strong contraction nozzle, and expansion ratio; and turbulence parameters; uncertain; and DS in laminar jets; turbulent nonswirling jets, and turbulent swirling jets are discussed.
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, FLOW DISTRIBUTION, RECIRCULATIVE FLUID...
Activities undertaken during the entire course of research are summarized. Studies were concerned with experimental and theoretical research on 2-D axisymmetric geometries under low speed nonreacting, turbulent, swirling flow conditions typical of gas turbine and ramjet combustion chambers. They included recirculation zone characterization, time-mean and turbulence simulation in swirling recirculating flow, sudden and gradual expansion flowfields, and furher complexities and parameter...
Topics: NASA Technical Reports Server (NTRS), COMBUSTIBLE FLOW, COMBUSTION CHAMBERS, FLOW DISTRIBUTION,...
A four-equation model of turbulence is applied to the numerical simulation of flows with massive separation induced by a sudden expansion. The model constants are a function of the flow parameters, and two different formulations for these functions are tested. The results are compared with experimental data for a high Reynolds-number case and with experimental and DNS data for a low Reynolds-number case. The computations prove that the recovery region downstream of the massive separation is...
Topics: NASA Technical Reports Server (NTRS), BACKWARD FACING STEPS, FLOW CHARACTERISTICS, MATHEMATICAL...
A new form of self-confined flow was investigated in which a recirculation zone forms away from any solid boundary. An inviscid flow analysis indicated that in a purely meridional axisymmetric flow a stationary, spherical, self-confined region should occur in the center of a streamlined divergent-convergent enlargement zone. The spherical confinement region would be at rest and at constant pressure. Experimental investigations were carried out in a specially built test apparatus to establish...
Topics: NASA Technical Reports Server (NTRS), FLUID FLOW, VORTEX RINGS, VORTICES, CONFINEMENT, FLOW...
A primitive pressure-velocity variable finite difference computer code was developed to predict swirling recirculating inert turbulent flows in axisymmetric combustors in general, and for application to a specific idealized combustion chamber with sudden or gradual expansion. The technique involves a staggered grid system for axial and radial velocities, a line relaxation procedure for efficient solution of the equations, a two-equation k-epsilon turbulence model, a stairstep boundary...
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, COMPUTER PROGRAMS, ISOTHERMAL PROCESSES,...
The effect of fuel injection technique on the performance of an advanced reverse flow combustor liner constructed of Lamilloy (a multilaminate transpiration type material) was determined. Performance and emission levels are documented over a range of simulated flight conditions using simplex pressure atomizing, spill return, and splash cone airblast injectors. A parametric evaluation of the effect of increased combustor loading with each of the fuel injector types is obtained.
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, COOLING, FUEL INJECTION, GAS TURBINES,...
The overall objective of the Turbine Engine Hot Section Technology Combustion Project was to develop and verify improved and more accurate numerical analysis methods for increasing the ability to design with confidence combustion systems for advanced aircraft gas turbine engines. The objective was approached from two directions: computational and experimental. On the computational side, the approach was to first assess and evaluate existing combustor aerothermal analysis models. On the...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT ENGINES, COMPUTERIZED SIMULATION, ENGINE DESIGN, GAS...
The performance of discrete methods for the prediction of fluid flows can be enhanced by improving the convergence rate of solvers and by increasing the accuracy of the discrete representation of the equations of motion. This report evaluates the gains in solver performance that are available when various acceleration methods are applied. Various discretizations are also examined and two are recommended because of their accuracy and robustness. Insertion of the improved discretization and...
Topics: NASA Technical Reports Server (NTRS), NUMERICAL ANALYSIS, RECIRCULATIVE FLUID FLOW, TURBULENT FLOW,...
Several Gurney flap configurations were tested in the NASA Langley 16 x 24 inch Water Tunnel. These devices provided an increased region of attached flow on a wing upper surface relative to the wing without the flaps. The recirculation region behind the flap was visualized and shown to be consistent with hypotheses stated in previous research. Although the test Reynolds number for this study was several orders of magnitude below those in previous investigations, the effect of the Gurney flaps...
Topics: NASA Technical Reports Server (NTRS), FLOW DISTRIBUTION, LIFT AUGMENTATION, LIFT DEVICES, WATER...
Scale model fuel heating systems for use with aviation hydrocarbon fuel at low temperatures were investigated. The effectiveness of the heating systems in providing flowability and pumpability at extreme low temperature when some freezing of the fuel would otherwise occur is evaluated. The test tank simulated a section of an outer wing tank, and was chilled on the upper and lower surfaces. Turbine engine lubricating oil was heated, and recirculating fuel transferred the heat. Fuels included: a...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT FUEL SYSTEMS, AIRCRAFT FUELS, HEATING EQUIPMENT, JET...
A multiple-scale turbulence closure scheme is developed for the numerical predictions of confined recirculating flows. This model is based on the multiple-time-scale concepts of Hanjalic et al. (1980) and takes into account the non-equilibrium spectra energy transfer mechanism. Problems concerning new formulation of energy transfer rate equations and subsequent model coefficient redefinition and energy spectrum partition are discussed. Comparisons are made with several experiments of internal...
Topics: NASA Technical Reports Server (NTRS), CLOSURE LAW, COMPUTATIONAL FLUID DYNAMICS, ENERGY SPECTRA,...
The central feature in any flow prediction method is the treatment of the coupling between the momentum and continuity equations. In natural-convection flows, the energy equation also becomes strongly coupled with the momentum equations. Because of the nonlinear nature of the coupling, these equations are solved iteratively. Iterative methods are often prone to slow convergence, divergence, and extreme sensitivity to underrelaxation factors. The aim of the present research is to develop more...
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, FLOW EQUATIONS, GAS TURBINE ENGINES,...
The structure of fuel sprays in a combustion chamber is theoretically investigated using computer models of current interest. Three representative spray models are considered: (1) a locally homogeneous flow (LHF) model, which assumes infinitely fast interphase transport rates; (2) a deterministic separated flow (DSF) model, which considers finite rates of interphase transport but ignores effects of droplet/turbulence interactions; and (3) a stochastic separated flow (SSF) model, which considers...
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, FUEL SPRAYS, GAS TURBINE ENGINES,...
The behavior of several turbulence models applied to the prediction of scramjet combustor flows is described. These models include the basic two equation model, the multiple dissipation length scale variant of the two equation model, and the algebraic stress model (ASM). Predictions were made of planar backward facing step flows and axisymmetric sudden expansion flows using each of these approaches. The formulation of each of these models are discussed, and the application of the different...
Topics: NASA Technical Reports Server (NTRS), FUEL COMBUSTION, SUPERSONIC COMBUSTION RAMJET ENGINES,...
The capability and the accuracy of the STARPIC computer code in predicting confined turbulent swirling recirculating flows is presented. Inlet flow boundary conditions were demonstrated to be extremely important in simulating a flowfield via numerical calculations. The degree of swirl strength and expansion ratio have strong effects on the characteristics of swirling flow. In a nonswirling flow, a large corner recirculation zone exists in the flowfield with an expansion ratio greater than one....
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, PREDICTION ANALYSIS TECHNIQUES,...
The objective of the present study is to improve both the accuracy and computational efficiency of existing numerical techniques used to predict viscous recirculating flows in combustors. A review of the status of the study is presented along with some illustrative results. The effort to improve the numerical techniques consists of the following technical tasks: (1) selection of numerical techniques to be evaluated; (2) two dimensional evaluation of selected techniques; and (3) three...
Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL FLUID DYNAMICS, PREDICTION ANALYSIS TECHNIQUES,...
The improvement of capabilities for computer simulation of turbulent recirculating flows was investigated. Attention has been limited to two dimensional flows and principally to statistically stationary motion. Improvement of turbulence modeling explored the treatment of the near wall sublayer and of the exterior fully turbulent region, working within the framework of turbulence closures requiring the solution of transport equations for the turbulence energy and its dissipation rate. The work...
Topics: NASA Technical Reports Server (NTRS), RECIRCULATIVE FLUID FLOW, TURBULENT FLOW, TURBULENT MIXING,...
Acoustic measurements from a hovering full scale XV-15 tilt rotor with the advanced technology blades are presented which show the directionality of fountain effect noise. Predicted acoustic directivity results are also presented which show agreement with the measured data. The aeroacoustic code, WOPWOP, was used in conjunction with a mathematical model which simulated the fountain recirculation aerodynamic effect on the rotor blade surface pressures. The predictions were used to identify the...
Topics: NASA Technical Reports Server (NTRS), AEROACOUSTICS, DIRECTIVITY, FLOW DISTRIBUTION, HOVERING,...
The flow field inside a whirling annular seal operating a Reynolds numbers of 12,000 and 24,000 and a Taylor number of 6,600 was measured. The rotor was mounted eccentric (50 percent) upon the facilities shaft which resulted in a circular orbit at a whirl ratio of 1.0. Three papers which summarize the work were written and are presented. Addition measurements were performed for the annular seal operating at an eccentricity ratio of 10 percent for Re = 24,000 and Ta = 6,600. A labyrinth seal was...
Topics: NASA Technical Reports Server (NTRS), COMPRESSIBLE FLUIDS, DYNAMIC RESPONSE, DYNAMIC STABILITY,...
The effective performance of modular thrusters in an aerospike configuration is difficult to determine. Standard analytical tools are applicable to conventional nozzle shapes, but are limited when applied to an aerospike nozzle (An aerospike nozzle is an altitude compensating external nozzle). Three baseline nozzle shapes are derived using standard analytical procedures. The baseline nozzle sizes are restricted to fill a volume envelope. The three shapes are an axi-symmetric round nozzle, a two...
Topics: NASA Technical Reports Server (NTRS), FLOW DISTRIBUTION, NAVIER-STOKES EQUATION, NOZZLE GEOMETRY,...
The difficulties of modeling the complex recirculating flow fields produced by multiple jet STOVL aircraft close to the ground have led to extensive use of experimental model tests to predict intake Hot Gas Reingestion (HGR). Model test results reliability is dependent on a satisfactory set of scaling rules which must be validated by fully comparable full scale tests. Scaling rules devised in the U.K. in the mid 60's gave good model/full scale agreement for the BAe P1127 aircraft. Until...
Topics: NASA Technical Reports Server (NTRS), EXHAUST GASES, INGESTION (ENGINES), SCALING LAWS, SHORT...
Current and proposed high speed aircraft have high leading edge heat transfer (to 160 MW/sq m, 100 Btu/sq in/sec) and surface temperatures to 1370 K (2000 F). Without cooling, these surfaces could not survive. In one proposal the coolant hydrogen is circulated to the leading edge through a passage and returned to be consumed by the propulsion system. Simulated flow studies and visualizations have shown flow separation within the passage with a stagnation locus that isolates a zone of...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC HEAT TRANSFER, BRUSHES, CONVECTIVE HEAT TRANSFER,...
The non-reacting flow produced by two confined, co- and/or counter-swirling jets wre measured by means of a two-color laser Doppler velocimeter. These results are compared with earlier experiments and with numerical predictions. It is shown that under both swirl conditions, a closed recirculation zone is created at the combustor center line. This zone is characterized by the presence of a one-cell toroidal vortex, low tangential velocities, high turbulent intensity, and large dissipation rates...
Topics: NASA Technical Reports Server (NTRS), COMBUSTION, COMPUTATIONAL FLUID DYNAMICS, MATHEMATICAL...
An axisymmetric swirling confined jet flowfield, similar to that encountered in gas turbine combustors was investigated using a triple hot-wire probe. The raw data from the three sensors were digitized using ADC's and stored on a Tektronix 4051 computer. The data were further reduced on the computer to obtain time-series for the three instantaneous velocity components in the flowfield. The time-mean velocities and the turbulence quantities were deduced. Qualification experiments were performed...
Topics: NASA Technical Reports Server (NTRS), FLOW VELOCITY, HOT-WIRE FLOWMETERS, RECIRCULATIVE FLUID FLOW,...
The time mean and turbulence properties of a confined swirling jet using the six orientation, single hot wire technique were obtained. The effect of swirl on a confined, expanding jet is to reduce the size of the corner recirculation zone and generate a central recirculation zone followed by a precessing vortex core. The effect of introducing a contraction nozzle of area ratio four, located two test section diameters downstream of the inlet, is to dramatically reduce the size and shape of the...
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, FLOW DISTRIBUTION, SWIRLING, THREE...
Steady flow over the leading portion of a multicomponent airfoil section is studied using computational fluid dynamics (CFD) employing an unstructured grid. To simplify the problem, only the inviscid terms are retained from the Reynolds-averaged Navier-Stokes equations - leaving the Euler equations. The algorithm is derived using the finite-volume approach, incorporating explicit time-marching of the unsteady Euler equations to a time-asymptotic, steady-state solution. The inviscid fluxes are...
Topics: NASA Technical Reports Server (NTRS), AIRFOIL PROFILES, COMPUTATIONAL FLUID DYNAMICS, COMPUTATIONAL...
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163
May 22, 2011
05/11
by
NON
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The present invention relates to a multicellular, three-dimensional, living mammalian tissue. The tissue is produced by a co-culture process wherein two distinct types of mammalian cells are co-cultured in a rotating bioreactor which is completely filled with culture media and cell attachment substrates. As the size of the tissue assemblies formed on the attachment substrates changes, the rotation of the bioreactor is adjusted accordingly.
Topics: AIRCRAFT ICING, BOUNDARY LAYER TRANSITION, NAVIER-STOKES EQUATION, REATTACHED FLOW, REYNOLDS...
A recently developed multiple scale turbulence model is used for the numerical prediction of isothermal, confined turbulent swirling flows. Because of the streamline curvature and nonequilibrium spectral energy transfer nature of the swirling flow, the utilized multiple scale turbulence model includes a different set of response equations for each of the large scale energetic eddies and the small scale transfer eddies. Predictions are made of a confined coaxial swirling jet in a sudden...
Topics: NASA Technical Reports Server (NTRS), JET FLOW, MATHEMATICAL MODELS, RECIRCULATIVE FLUID FLOW,...
