The purposes of this research were to implement the circular plume model developed by Wuest et al. (1992) and to develop and verify a linear plume model based on the circular model. The linear model developed is the first that models a bubble plume generated by a linear source in thermally stratified water and considers the effects of gas transfer between the bubbles and surrounding water. The basis for both models is eight differential flux equations which are solved numerically using Euler’s method. Knowledge of ambient temperature, dissolved solids, dissolved oxygen, and dissolved nitrogen profiles as well as gas input rate, diffuser dimensions, and initial bubble size are required to implement the models. The implementation of the circular model was successful as the results obtained corresponded with those reported by Wuest et al. (1992). The linear model made predictions very similar to those made by the circular model and, therefore, was also considered to perform well. Comparisons of the linear model with available data met with limited success. Initially, the linear model’s predictions of laboratory scale plume velocity data resulted in overpredictions of 40 to 50 percent when compared to actual data. Error in predictions of laboratory scale oxygen transfer data were greater than 100 percent. The model fared better when its predictions were compared to full scale data; the predicted temperature was within 7 percent of that measured at three depths and the predicted oxygen concentration was within 4, 20, and 38 percent for the three depths. Some of the discrepancies in the data likely result from the fact that the Froude number used in the model to calculate initial velocity was derived for a circular, rather than a linear, source. Determination of the appropriate linear Froude number would likely improve the model’s predictions. / Master of Science

Orientadores: Carlos Kenichi Suzuki, Aron José Pazin de Andrade / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-21T07:29:25Z (GMT). No. of bitstreams: 1 Silva_BrunoUtiyamada_M.pdf: 3089036 bytes, checksum: 01d1bb268591e2388a9bb34046fbd188 (MD5) Previous issue date: 2012 / Resumo: Neste trabalho, foi realizado um estudo experimental de uma Bomba de Sangue Ápice Ventricular (BSAV) para sua análise como um dispositivo de assistência ventricular. Este estudo faz parte do desenvolvimento desta bomba e serviu como fundamentação na evolução do projeto. A BSAV é uma bomba de sangue centrífuga de fluxo contínuo, para ser utilizada como dispositivo de assistência ventricular em pacientes com doenças cardíacas crônicas. Foi realizado um estudo de posicionamento anatômico, onde a bomba foi implantada em um coração de um porco e não foram encontrados indícios de possíveis danos aos tecidos e órgãos circunvizinhos. Em seguida, foi feito um ensaio experimental, onde foi comparado o desempenho de protótipos com características distintas, visando sua otimização em relação ao desempenho hidrodinâmico. Também foi realizado um estudo para avaliação do trauma as células do sangue causado pela ação da bomba, no qual os resultados mostraram um baixo dano as células. A seguir, foi feito estudo com um protótipo conectado em um simulador cardiovascular híbrido (matemático e físico), onde este protótipo às condições simuladas de um sistema cardiovascular com insuficiência cardíaca. Com a BSAV conectada ao sistema obteve-se, uma melhora no fluxo de sangue, frequência cardíaca e pressão aórtica. Os resultados indicam que a BSAV é adequada para aplicação como dispositivo de assistência ventricular esquerda e é uma alternativa promissora no tratamento de pacientes com doenças cardíacas crônicas / Abstract: In this work an experimental study was realized with the Apico-Ventricular Blood Pump (AVBP) used as a ventricular assist device. This study is part of the device's development and the results were used for project evaluation and improvement. AVBP is a continuous flow centrifugal blood pump for ventricular assistance in chronic cardiac patients. Initially, an anatomic study was performed, in this study an AVBP prototype was implanted in a corpse of a pig, the clinical staff appointed, none damage to the nearby tissues and organs due to the contact with the device. Following step consists in an experimental hydrodynamic performance test. For this test the prototypes used had distinct specific construction characteristics variations among themselves, for device optimization, the performance of these different prototypes were compared, and the prototypes which presented a better performance had their characteristic adopted in the project. A study to determine the traumatic effect of the pump on blood cells was conducted, the results showed low damage to the blood cells. A hybrid mock loop circulation system (mathematical and physic) where the pump, was connected to a system with heart disease, was used. When the AVBP was inserted in the system, cardiac output, heart rate and aortic pressure went to normal values. All results indicated the performance of the AVBP as ventricular assist device, an alternative for treatment of patients with cardiac chronic diseases / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica