Thesis (M.S.)--Rochester Institute of Technology, 1988. / Typescript. Includes bibliographical references (leaves 97-98).

Made available in DSpace on 2014-06-11T19:30:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02Bitstream added on 2014-06-13T20:00:03Z : No. of bitstreams: 1 tofoli_f_me_guara.pdf: 778310 bytes, checksum: 518b10e7c88d6a576eb683e42128bcd4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho tem como objetivo a análise da influência de parâmetros adimensionais e grandezas dimensionais no projeto de turbomáquinas operando em diferentes situações de pressão, temperatura e vazão mássica de vapor. O trabalho é divido em duas partes principais, sendo que inicialmente são analisados os parâmetros adimensionais e as grandezas dimensionais que influenciam diretamente o valor do rendimento interno das turbomáquinas térmicas que utilizam o vapor como fluido de trabalho. Na segunda parte do trabalho são abordadas as classes de pressão e rotação específica, e sua influência no comportamento de parâmetros adimensionais. A aplicação dos resultados está diretamente ligada a especificação de turbomáquinas em sistemas de cogeração para aproveitamento de fluxos térmicos provenientes de processos, queima de combustíveis ou gases de escape de uma máquina térmica, para os quais os projetistas necessitam estimar o rendimento de tais componentes por ocasião da análise de viabilidade econômica. / This work has as objective the analysis of the influence of dimensionless parameters and dimensional greatness in the project of turbomachinery operating in different pressure situations, temperature and flow steam. This work is shared in two main parts, which are initially analyzed the dimensionless parameters and the dimensional greatness that directly influence the internal efficiency of the thermal turbomachinery that using steam as the working fluid. In the second part of the work are accosted the classes of pressure and specific rotation, and its influence on the behavior of dimensionless parameters. The application of the results is directly linked to the specification of turbomachinery in cogeneration systems for use of heat flows from processes, burning of fuel or the exhaust gases of a thermal machine, for which the designers needs to estimate the efficiency of such components at analysis of economic feasibility.

No description available.

Through this thesis evidence will be collected to determine the need of a proposed turbo-generator and boiler unit adequate for future requirements of the campus and community of Blacksburg. / Master of Science

Generally it is believed that in a power station when there is a demand for process steam and also demand for heating, most of the auxiliaries of the plant should be arranged to be driven by steam rather than using electrical energy for them. This is, however, a general remark and a correct selection can be made only after a detailed study is made of all factors involved. The V. P. I. central heating and power plant works mainly as a heating station, generation of electrical energy, being a by-product. So this problem is completely different from the standpoint of a general power station. This station supplies heating steam to the college through two different pressure lines. One is the low pressure, and the other is the high pressure line. / Master of Science

The objective of this project is to optimize the SAPREF oil refinery steam distribution in which imbalances between the various levels presently require the venting of steam from the lowest level. The overall steam balance shows that the problem originates from an excess of high·pressure (HP) steam production for too few medium pressure steam users and turbines. We proposed to solve this problem by considering the replacement of selected steam turbines with electrical drives. Given a set of demands of electricity, mechanical power and steam at various pressure levels, the objective is to recommend configuration changes to minimize overall cost. This is not a trivial problem, as steam not passed down through turbines to lower levels can create a shortage there, so a combination of replacements is required. The variables of the problem are both decision variables on every steam turbine and continuous variables, such as flows and enthalpies. These decision variables are integer variables, 0 or 1 for every steam turbine. Depending on whether it is kept on steam use or replaced with an electrical drive, these variables are as follows: E = 0: keep the existing steam turbine E - 1: switch it to an electrical drive. A complete and realistic model of this utility section must be constructed in order to represent the actual distribution accurately. This model will include an objective function to minimize, some equality and inequality constraints, and some cost functions. If we want this model to be accurate, we shall have to deal with nonlinearities to avoid simplifications, and these non-linearities could lead to infeasabilities or sub-optimal solutions. So we are facing a typical MTNLP (Mixed Integer Non-Linear Programming) problem to find optimal configuration changes which will maximize the return on investment, meeting the electrical, mechanical and steam demands of the refinery. In order to solve this difficult optimization problem we shall use the user-friendly package GAMS (General Algebraic Modeling System). / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.

Resumo: Este trabalho tem como objetivo a análise da influência de parâmetros adimensionais e grandezas dimensionais no projeto de turbomáquinas operando em diferentes situações de pressão, temperatura e vazão mássica de vapor. O trabalho é divido em duas partes principais, sendo que inicialmente são analisados os parâmetros adimensionais e as grandezas dimensionais que influenciam diretamente o valor do rendimento interno das turbomáquinas térmicas que utilizam o vapor como fluido de trabalho. Na segunda parte do trabalho são abordadas as classes de pressão e rotação específica, e sua influência no comportamento de parâmetros adimensionais. A aplicação dos resultados está diretamente ligada a especificação de turbomáquinas em sistemas de cogeração para aproveitamento de fluxos térmicos provenientes de processos, queima de combustíveis ou gases de escape de uma máquina térmica, para os quais os projetistas necessitam estimar o rendimento de tais componentes por ocasião da análise de viabilidade econômica. / Abstract: This work has as objective the analysis of the influence of dimensionless parameters and dimensional greatness in the project of turbomachinery operating in different pressure situations, temperature and flow steam. This work is shared in two main parts, which are initially analyzed the dimensionless parameters and the dimensional greatness that directly influence the internal efficiency of the thermal turbomachinery that using steam as the working fluid. In the second part of the work are accosted the classes of pressure and specific rotation, and its influence on the behavior of dimensionless parameters. The application of the results is directly linked to the specification of turbomachinery in cogeneration systems for use of heat flows from processes, burning of fuel or the exhaust gases of a thermal machine, for which the designers needs to estimate the efficiency of such components at analysis of economic feasibility. / Orientador: Paulo Magalhães Filho / Coorientador: José Nédilo Carrinho de Castro / Banca: Carlos Daniel Ebinuma / Banca: José Rui Camargo / Mestre

No description available.

No description available.

A cogeneration system using a noncondensing steam turbine to simultaneously provide electricity and process steam to a citrus plant was modeled in order to assess the source energy savings and the economic implications with the employment of this type system under conditions of time varying plant energy demand. Average monthly energy demand data from on citrus plant was analyzed. It was determined that the important parameter, in addition to a minimum demand level, for assessing economic acceptability is the demand thermal to electric ratio. One set of steam conditions will not necessarily provide the maximum source energy savings and at the same time be the most economically beneficial. The values of the economic criteria will remain relatively constant over a range of rated turbine capacities for each set of steam conditions.