Listagem por temas:

Escolhendo um título você terá acesso ao arquivo original em Post-Script.

COB306 TERMOQUÍMICA DOS PRODUTOS DE COMBUSTÃO UTILIZANDO PROPRIEDADES TERMODINÂMICAS OBTIDAS DA MECÂNICA ESTATÍSTICA / TERMOCHEMICAL OF COMBUSTION PRODUCTS USING THERMODYNAMIC PROPERTIES OBTAINED OF STATISTICAL MECHANICS

Carlos Alberto Rocha Pimentel^{( 1 )}, José Nivaldo Hinckel^{( 2 )} & Jorge Koreeda^{( 2 )}

^{( 1 )} Instituto de Engenharia Aeronáutica - IEA, Instituto Tecnológico de Aeronáutica - ITA

CEP 12228 - 900 São José dos Campos, SP Brasil - E - mail: carlosal@aer.ita.cta.br

^{( 2 )} Divisão de Mecânica Espacial e Controle, Instituto Nacional de Pesquisas Espaciais - INPE

Av. dos Astronautas 1758, Caixa Postal 515 CEP 12201-970 São José dos Campos, SP Brasil -

E - mail: hinckel@sigma.dem.inpe.br

This work presents the results of an analytical model and a computer program to obtain thermochemical properties of combustion products in a liquid rocket motors, using the method of statistical mechanic to calculation thermodynamic properties of the species. The equations of statistical mechanics and the technique of minimization of Gibbs free energy are used to calculate the thermochemical functions and the equilibrium chemical composition. These methods are applied to the calculation of equilibrium properties of the combustion products in liquid rocket motors for different propellant pairs, O/F ratios and chamber pressures. The results obtained from this method are compared to those of NASA SP-273.

Keywords: Combustion products - equilibrium chemical composition - statistical mechanics - minimization of Gibbs free energy - liquid fuel / Produtos de combustão - Composição em equilíbrio químico - Mecânica estatística - Minimização da energia livre de Gibbs - Combustível líquido

COB323 INCINERAÇÃO DE RESÍDUOS SÓLIDOS DE SERVIÇOS DE SAÚDE UTILIZANDO O BIOGÁS DE ATERROS SANITÁRIOS / MEDICAL WASTES INCINERATION WITH UTILIZATION OF THE BIOGAS GENERATED FROM SANITARY LANDFILLS.

Celso Luiz da Silva (*) & Enric Velo (**)

(*) Departamento de Engenharia Mecânica, FET / UNESP - Bauru/BR - E-mail: celsos@azul.bauru.unesp.br

(**)Departamento de Máquinas y Motores Térmicos, ETSEIB / UPC - Barcelona/ES

08028 - Av. Diagonal, 647, 7º, Barcelona, España - E-mail: enric@mmt.upc.es

This paper takes consideration about the utilisation of the biogas generated from sanitary landfills as a support energy source on medical wastes incineration processes. The data from similar incinerators currently operating in Brasilian cities and data bibliography has used. The results of the present study shows the volume of the biogas necessary for operating system as function of the habitants number.

Keywords: Incineração -Biogás - Resíduos - Combustão - Energia - Incineration - Medical Wastes - Combustion - Energy

COB525 CONSIDERAÇÕES SOBRE A RELEVÂNCIA DOS 3T`s NA INCINERAÇÃO DE RESÍDUOS ORGÂNICOS./ CONSIDERATION CONCERNING ON THE 3T`s SIGNIFICANCE IN THE ORGANIC RESIDUES INCINERATION

José Claudio Moura & Moacir José Bufo

Departamento de Processos Químicos, Faculdade de Engenharia Química - UNICAMP

CEP 13083-970 Campinas, Brasil - E-mail: moura @ feq.unicamp.br

We discuss the 3T`s (Temperature, Residence time and Turbulence) real importance on the organic compounds incineration, trying to show that the temperature importance over 850 ^oC, after thermal decomposition (Pyrolysis) and partial combustion of the organic componds, the carbon monoxide combustion defines the ligh temperature needs. But, arround 910 ^oC, 2 seconds of residence time puts the conversion over the four nines (99,99 %) pattern fixed by the present regulation, NB-1265, for incineration performance. If we attend these conditions, the principal goal on incineration of organic componds is attained by the best turbulence.

Keywords: Incineração, Importância dos 3T`s, ABNT NB 1265, Pirólise, Monóxido de carbono. Incineration, Pyrolisis, 3T`s Combustion, ABNT NB 1265, Carbon monoxide..

COB540 SISTEMA DE COLETA E ANÁLISE DE GASES E ALCATRÕES DE GASEIFICADORES / A LABORATORY TYPE TAR GAS AND PARTICULATE SAMPLING UNIT

Ricardo De Leon Pereira, Caio Glauco Sánchez

Departamento de EngenhariaTérmica e de Fluídos, Faculdade de Engenharia Mecânica, UNICAMP, Campinas, SP, Caixa Postal 6088, 13083-970 E-mail: caio@fem.unicamp.br

A laboratory type tar and particulate sampling unit has been designed for quantitative assesment of contaminant in biomass based producer gas. Development of efficient cleaning system is an important facet of biomass gasification technology.

Keywords: Isocinetic sampling unit, Tar, Gaseification, Gas cleaning, Amostragem isocinética; Alcatrão; Limpeza de gás; Gaseificação

COB1098 CO-PROCESSAMENTO DE RESÍDUOS PERIGOSOS EM FORNOS ROTATIVOS DE FÁBRICAS DE CIMENTO / CO-INCINERATION OF HAZARDOUS WASTES IN THE ROTARY KILNS OF CEMENT INDUSTRY

Andréa Paula Ottoboni & Rogério José Da Silva

Departamento de Engenharia Mecânica, Escola Federal de Engenharia de Itajubá – EFEI – Itajubá

CEP 37500-000 Itajubá, Brasil – E-mail: rogerio@iem.efei.rmg.br

The co-processing of waste in rotary kiln enables theirs thermal destruction and the simultaneous utilization of generated heat in process of production of clinker. This technology has received a special attention, because the great advantage which it offers under the technical, scientific and economic viewpoints. The work presents a thermal valuation this process by analyzing of production process, searching to identify the level of formation of by-products and the emission of pollutants to the atmosphere. In addition, it's also analyzed the chemical kinetics through the reactions of decomposition of residual substances, based on Arrehniu's equation. Thus, it's possible preliminary, to obtain the necessary residence time to reach high level of efficiency thermal destruction of the waste in verified temperatures in inner of rotary kilns of the cement plants.

Keywords: Cement Kiln, Hazardous Waste, Rotary Kiln, Co-Incineration,Thermal Destruction .

Forno de Cimento, Resíduo Perigoso, Forno Rotativo, Co-Processamento, Destruição Térmica

COB1113 MODELO SIMPLIFICADO PARA A VAPORIZAÇÃO DE GOTAS DE COMBUSTÍVEL EMULSIFICADO / SIMPLIFIED MODEL FOR VAPORIZATION OF EMULSIFIED FUEL DROPLETS

Luiz Fernando Teixeira Leite & Paulo Laranjeira da Cunha Lage

Programa de Engenharia Química, COPPE-UFRJ-Ilha do Fundão

CEP 21.945-970 Ilha do Fundão, Brasil - E-mail: paulo@peq.coppe.ufrj.br

A model for the vaporization of emulsified fuel droplets has been developed by assuming transient-diffusive heat transport and constant liquid composition within the droplet. For the gas-phase, the extended film theory has been used. The model is used to simulate de vaporization of water-in-hexadecane emulsion droplets in order to study the microexplosion phenomena. It has been shown that, although some trends are well predicted, the influence of the initial mass fraction of water on the relative time for the occurrence of microexplosion is wrongly predicted by the model. The reason seems to be the inconsistency of the constant liquid composition hypothesis.

Keywords: Emulsified fuel, microexplosion, superheated emulsion, droplet vaporization. Combustível emulsificado, microexplosão, emulsão superaquecida, vaporização de gotas.

COB1241 CONTROLE DAS EMISSÕES DE NO_X EM MOTORES DIESEL MARÍTIMOS / NO_X EMISSION CONTROL IN MARINE DIESEL ENGINES

Alexandre Teixeira P. Alho⁽¹⁾ & Silvio Carlos A. Almeida⁽²⁾

⁽¹⁾ Departamento de Engenharia Naval, Escola de Engenharia - UFRJ

⁽²⁾ Departamento de Engenharia Mecânica, Escola de Engenharia - UFRJ - CEP 21.945-970, Ilha do Fundão, Rio de Janeiro, Brasil

E-mail: alho@peno.coppe.ufrj.br

In recent years, an increasing awareness of the contribution of marine exhaust emissions to atmospheric pollution has been observed, with particular attention on the emission of nitrogen oxides, NO_X. This concern is reflected in the high priority established by the International Maritime Organization (IMO), as well as several countries, in the implementation of restrictions on emissions from marine sources. This paper discusses the principal aspects related to NO_X emission control of marine diesel engines. Some of the control methods developed by engine builders are reviewed with respect to their efficiency and related problems on engine operation. Future prospects of each proposed solution are evaluated in view of social demand for more restrictive emissions limits.

Keywords: Diesel, Combustão, Emissões, Controle, Poluição - Diesel, Combustion, Emissions, Control, Pollution

COB1243 AN ANALYTICALLY GENERATED GRID FOR DROPLET-STREAM COMBUSTION PROBLEMS

Albino J.K. Leiroz \Lambda & Roger H. Rangel

Department of Mechanical and Aerospace Engineering, University of California, Irvine -- Irvine, CA 92697-3975 USA

The present work describes the development of a discretizing grid for the numerical study of droplet stream combustion problems. The small and large length scale phenomena associated with the process are addressed by splitting the physical domain into near and far-field subdomains. Within the inner subd-omain, expressions previously developed for droplet-stream vaporization studies are used allowing the development of appropriate finite-difference expressions and control of grid point distribution. Analytical expression are developed and applied to the outer subdomain coordinate system in order to match the inner and outer grids along the subdomain interface and to properly address the out-flow boundary conditions using a regularly spaced grid. The proposed extension of the numerical approach previously used is made necessary by the singularity present in the coordinate transformation which becomes important as high aspect ratio domains are studied. The singularity affects the results leading to nonrealistic velocity profiles at the droplet surface. Quasi-steady and transient results, which indicate interaction effects present over a broad range of interdroplet distances, are also presented.

Keywords: Combustion, Vaporization, Phase-Change, Numerical Methods, Grid Generation.

COB1247 FRENTE DE CHAMA: MODELAGEM E PESQUISA DAS CARACTERISTICAS DETALHADAS / FRONT OF FLAME: RESEARCH AND MODELING OF DETAILS CHARACTERISTICAS

Ickhakova Raissa, Denise Knorst, Abdulline Airat

Mestrado em Modelagem Matemática - UNIJUI, CD 560 98.700-000 Ijuí/RS, Brasil, E-mail: infpgm@super.unijui.tche.br

Departamento de ciências térmicas - KGTU, CP 420111 Kazan/Tatarstan, Rússia, Email: naumov@kaidla.ksu.ras.ru

The present work propose a form of the thermal model equations that not use the boundary conditions on the - "hot" limit. One too apply the exponential form of the chemical kinetics equations.The corresponding algorithm and program are invariant to reagent medium. The numerical results to fuel: CH₄ + air; C₃H₈ + air are shown.

Keywords: Frente de chama, modelo térmico, substâncias intermediárias, entalpia / Front of flame, thermal model, intermediate substance, entalpia

COB1249 PESQUISA TEÓRICA DOS ESCOAMENTOS QUIMICAMENTE DESEQUILIBRADOS EM TUBEIRAS SUPERSÔNICAS / THEORETICAL RESEARCH OF UNEQUILIBRIUM CHEMICALLY FLOW IN SUPERSONICS NOSSELS

Krioukov Viktor, Trinos Taras

Mestrado em Modelagem Matemática - UNIJUI ,CP 560 98700-000 Ijuí/RS, Brasil, E-mail: kriukov@super.unijui.tche.br

Departamento de Ciências Térmicas - KGTU, CP 420111 Kazan/ Tatarstan, Rússia, E-mail: trinos@kaidla.ksu.ras.ru

The present work study the model of the unequilibrium chemically current in supersonic nossel.The advantage of this model is the possibility to calculate the proprieties of the currents as much gaseous as condensed phase. One describe the algorithm and program that are invariant to reagent medium . The numerical results to many fuel are shown.

Keywords: Tubeiras, escoamento, cinética química, modelagem. / Nossels, current, chemical kinetic, modeling.