Thesis (M. S.)--Chemical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Allen, Mark; Committee Member: Allen, Sue Ann Bidstrup; Committee Member: Wong, C.P.

Thesis (Ph. D.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xiv, 256 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 118-122).

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Neste trabalho pretende-se desenvolver o dispositivo para a fixação de cabeçotes e acionamento de válvulas em um equipamento para medição de swirl, que é um dos movimentos do ar dentro da câmara de combustão nos motores de ignição por compressão. Este desenvolvimento tem como objetivos facilitar a montagem do cabeçote no equipamento e desenvolver o avanço automático das válvulas, visando a redução do tempo total do ensaio. No desenvolvimento, foi feito um comparativo das características e componentes montados nos cabeçotes e nos diferentes modelos que serão testados no equipamento, para que não fossem necessários retrabalhos no cabeçote ou desmontagens de componentes para a realização dos ensaios, abrangendo a maior gama possível de produtos. Foram definidos os métodos de posicionamento do cabeçote no dispositivo e o sistema de fixação. Para garantir a precisão no acionamento das válvulas, foi definido um fuso de esferas recirculantes, acionadas por um motor de passo. O projeto foi concluído e o dispositivo foi fabricado e instalado no equipamento de medição. Testes realizados mostraram resultados de medição de swirl conforme esperado, além da diminuição no tempo total do teste. A partir de observações feitas após a fabricação e os testes no dispositivo, algumas melhorias estão sendo propostas, como, por exemplo, acionamentos por balancins independentes para cada válvula. / In this work, the aim is to develop the device for the fixture of the cylinder head and the valve actuation in a swirl meter test bench. Swirl is a movement inside the combustion chamber in a compression ignition engine. The development aims to facilitate the assembling of the cylinder head in the equipment and develop the valve lift device, focusing in decreasing the total time for the test. Also, the valve actuator shall be able to perform the continuous valve lift in the swirl measurement. During the development of this work, a comparative of the main features and the components assembled in the different cylinder head types to be tested in the equipment was done, to avoid rework or disassembling of components for the test, including the most variety of types. It was defined the positioning method for cylinder head in the device and the fixation system. To ensure the precision in the valve actuation, it was defined a ball screw, driven by a step motor. The project was finalized, manufactured and installed in the measurement equipment. Performed tests have showed results of swirl measurement according to expected, and the total time of test was decreased. After this first project, some improvements are proposed in the device, for example, individual actuation per valve.

Small Venturis were used to measure air flow rates through cigarette-making machines to a vacuum header. A programmable calculator was used to develop charts for each Venturi. showing flow versus differential pressure at inlet vacuums from 8 in. (203 mm) to 20 in. (508 mm) of mercury. Use of the charts eliminates the need to calculate the flow each time a test is run. An error analysis indicated that large variations in temperature do not affect the result. The accuracy of the charts is not affected as long as the tests are run at room temperature. The Venturis, ranging in size from ½ in. (13 mm) to l ½ in. (38 mm) will continue to be used to measure and monitor vacuum requirements of the machines. / Master of Engineering

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This thesis describes an experimental study of the air flow in ventilating ducts in the stators of electric motors and/or generators of conventional design. The objective was to facilitate prediction of local heat transfer coefficients in ventilating ducts. Various flow phenomena were observed and compared with theoretical predictions. While the theory usually used for similar cases was found o be inapplicable, a related theory was found that checked well with experimental results. A stall phenomenon was observed under certain identified conditions. Useful relationships for predicting the flow details were obtained. The relevance of the work is discussed and future work is proposed. / Thesis / Master of Engineering (MEngr)

An experimental study of turbulent air flow in a pipe is reported in this paper. A determination was made of the mean velocity distribution and longitudinal mean turbulent velocity distribution, both in the turbulent core and boundary layer for four different Reynolds numbers from 7300 to 58300. A traversing mechanism was designed in order to measure the turbulence correlations between two points. The variation of the macro scale length, one of the fundamental quantities in recent statistical turbulence theory across the pipe diameter was calculated for Reynolds number equal to 58300, by integrating the correlation curves. The turbulent momentum diffusivity at the center of a pipe was calculated from the correlation study and the dimension less value was found to be 0.111. Ethylene gas was injected into the center of the pipe, and in order to investigate the turbulent mass diffusivity, the concentration distribution curves of ethylene were measured at different test positions downstream from the injection point, for the same series of Reynolds numbers used in the turbulence measurement. A numerical method for calculating the diffusivity was developed. The values of diffusivity obtained. in these experiments show that the assumptions which were used by most of the authors, that of (turbulent mass diffusivity/turbulent momentum diffusivity) has a value between 1.0 to 1.6 is correct. / Thesis / Master of Engineering (ME)