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... Nacional de Fusion, EURATOM-CIEMAT, Madrid (Spain) Krupnik, L. Chmyga,

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A stable, accurate, and efficient implementation of MacCormack's explicit algorithm for the Parabolized Navier-Stokes equations is demonstrated. The familiar problem of decoding the conservative axial flux vector is solved, resulting in accurate, smooth dependent variable profiles through the viscous-layer sonic line. Source terms due to transformation of the parabolized governing equations into the computational plane and the equations into the computational plane and the resulting metric differencing have been identified and eliminated through inclusion of appropriate geometric conservation law terms. Test cases computed include two- and three-dimensional supersonic and hypersonic flow at laminar and turbulent Reynolds numbers. The computed results demonstrate very good agreement with experiment and with solutions of the full Navier-Stokes equations. Computational times required for the MacCormack explicit PNS code are approximately equal to those of the ...

International Nuclear Information System (INIS)

To illustrate frequently encountered anatomic variations on PNS computed tomography(CT) and to assess their clinical significance. CT findings of 1523 patients, who underwent PNS CT with no history of sinus surgery, were reviewed, and prevalence of each anatomic variation and its relationship with mucociliary clearance pathway was evaluated. Two categories of anatomic variations were encountered. The first group included variations of the turbinates, such as concha bullosa(28.6%), paradoxical middle turbinate(31.5%), of the uncinate process, such as medially bent or folded(36.3%), laterally bent(3.7%) or uncinate bulla(0.5%), of the ethmoidal sinus, such as Haller's cell(28.2%), large agger nasi cell(9.6%) or large ethmoidal bulla(23.5%) and nasal septal deviation(24.1%), which might cause obstruction of mucociliary clearance pathway and thus give rise to secondary obstructive sinusitis. The second group included Onodi cell(1.4%) and medial ...

Energy Technology Data Exchange (ETDEWEB)

A method to select, among several commercial diameter options, the most economic combination of pipeline networks is presented. These networks comply with the discharge conditions in the pipes and pressure in the knots. It is applied a static method for the hydraulics analysis of the Engineering Institute of the Universidad Nacional Autonoma de Mexico (UNAM) and an optimization technique to reduce the number of calculations. [Spanish] Se presenta un metodo para seleccionar, de entre varias opciones de diametros comerciales, la combinacion que forma la red de tuberias mas economica que satisface las condiciones de gasto en los tubos y de presion en los nudos de la misma. Para el analisis hidraulico se emplea un metodo estatico del Instituto de Ingenieria de la Universidad Nacional Autonoma de Mexico (UNAM) y se aplica una tecnica de optimacion para reducir el numero de calculos y alcanzar la solucion.

Energy Technology Data Exchange (ETDEWEB)

Secondary energy can be described as a surplus of electrical energy in a hydropower because the lower demand of energy in some period of the day and the excess of water in the reservoir during the rainy periods. This study proposes the using of the excess of energy at Itaipu Bi nacional for electrolytically hydrogen production and ammonia for nitrogenous fertilizers. Ammonia is a raw material for nitrogenous fertilizers synthesis and produced using hydrogen and nitrogen from the atmosphere. This paper determines the minimal cost of hydrogen production and the capacity of hydrogen production, with this data and according the ammonia market for nitrogenous fertilizers in the Centre/South region was estimated the better capacity of ammonia production for one plant near Itaipu. The process of ammonia production using energy excess is the most environmental acceptable. (author)

International Nuclear Information System (INIS)

This paper describes an electronic imaging system for producing real time neutron radiography from a low power research reactor, which will allow inspections of samples with high efficiency, in terms of measuring time and result analysis. This system has been implanted because of its potential use in various scientific and industrial areas where neutron radiography with photographic film could not be applied. This real time system is installed in neutron radiography facility of Argonauta nuclear research reactor, at the Instituto de Engenharia Nuclear of the Comissao Nacional de Energia Nuclear, in Brazil. It is adequate to perform real time neutron radiography of static and dynamic events of samples.

Energy Technology Data Exchange (ETDEWEB)

This document contains the technical proceedings of the 19 national seminar on the rational use of energy and exposition of equipment and services, organized by the Asociacion de Tecnicos y Pofesionistas en Aplicacion Energetica (ATPAE) (Association of Technicians and Professionals on Energy Application) conducted in Mexico City on September 21-25, 1998. This seminar encompassed subjects such as: energy saving in the energy sector, energy efficiency in industrial processes and practical developments, practical cases of energy saving in industry, energy saving in buildings, transportation, non-renewable energy utilization and environmental impact and eco-energies. [Espanol] Este documento contiene la memoria tecnica del 19 seminario nacional sobre el uso racional de la energia y exposicion de equipos y servicios, organizado por la Asociacion de Tecnicos y Profesionistas en Aplicacion Energetica (ATPAE), en Mexico, D.F, los dias 21-25 de septiembre de 1998. Este ...

Energy Technology Data Exchange (ETDEWEB)

Most of the information in this chapter is obtained from 1, 2, 3, 6, 8 and 9 annexes. It is worthwhile to clarify that in most of the cases they are estimations of the available resources, such as: trash, geothermal, solar energy, wind energy, biomass and mini and micro-hydro-energy. In several cases punctual measurements have been made, which do not represent a generic value of a national reserve. [Spanish] La mayor parte de la informacion en este capitulo es obtenida de los anexos 1, 2, 3, 6, 8 y 9. Cabe aclarar que en la mayoria de los casos son estimaciones de los recursos disponibles, tales como: la basura, la geotermia, la energia solar, la energia eolica, la biomasa y, la mini y la micro-hidroenergia. En varios casos se han realizado mediciones puntuales, las cuales no representan un valor generico de una reserva nacional.

International Nuclear Information System (INIS)

A study was performed to investigate the size of pharyngeal cavity and sexual differences between Korean adult mal e and female by introducing linear analysis of the lateral cephalogram. The radiograms were composed of 46 adult male aged 24.64 and 52 adult female aged 22.74 respectively. In order to study and measure the pharyngeal area, the following skeletal landmarks were selected: S,N,A,Ptm, B,H,H', M ,S-N, FH and CV, and the angle CV-FH was measured to provide a factor for correction of error resulting from improper he ad positioning of subjects, especially in the relative positions of A and H, while radiography. All points to be measured were projected at right angles to the Frankfort plane. For the purpose of measuring the anteroposterior dimensions of pharyngeal cavity the distances were measured in A-Ptm, A-S, S-Ptm and CV-H, and vertical measurements were made in SN-A, SN-PNS, SN-H' and M-H. The obtained results were as follows: 1. The pharyngeal cavity ...