Título: | STUDY ON THE DEGRADATION OF DRAG REDUCING POLYMERS IN TURBULENT FLOWS | ||||||||||||
Autor(es): |
IAN DE SOUZA COSENZA |
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Colaborador(es): |
IGOR BRAGA DE PAULA - Orientador |
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Catalogação: | 18/SET/2019 | Língua(s): | PORTUGUESE - BRAZIL |
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Tipo: | TEXT | Subtipo: | SENIOR PROJECT | ||||||||||
Notas: |
[pt] Todos os dados constantes dos documentos são de inteira responsabilidade de seus autores. Os dados utilizados nas descrições dos documentos estão em conformidade com os sistemas da administração da PUC-Rio. [en] All data contained in the documents are the sole responsibility of the authors. The data used in the descriptions of the documents are in conformity with the systems of the administration of PUC-Rio. |
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Referência(s): |
[pt] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/TFCs/consultas/conteudo.php?strSecao=resultado&nrSeq=45387@1 [en] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/TFCs/consultas/conteudo.php?strSecao=resultado&nrSeq=45387@2 |
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DOI: | https://doi.org/10.17771/PUCRio.acad.45387 | ||||||||||||
Resumo: | |||||||||||||
Drag reduction strategies are subject of deep interest for industry and other sectors of technology, since they can reduce energy expenses in several processes. The phenomenon of drag reduction by addition of
polymers was discovered by Toms in 1948 and has been studied by several researchers. Despite this, there is still no consensus about the physical mechanisms that govern the problem. This work aims at studying
drag reduction on turbulent pipe flows caused by the addition of polymers in different concentrations. In addition, it was observed the degradation of polymeric solutions with the residence time in the pipeline. It is known that the polymers can degrade due to shear, and this degradation is more pronounced when subjected to high shear stresses such as in pumps or valves. Therefore, a wheel-type test bench was used. This device consists of a pipe mounted on a wheel, forming a closed circuit. The device is oriented in the vertical direction. The pipe is partially filled with fluid and rotated over its axis. Thus, the walls of the tubing move and the fluid is concentrated in the lower part of the wheel. Depending on the speed of rotation the flow becomes turbulent. Thereby, a turbulent flow is obtained without it passing through pumps, and thus it is possible to evaluate the degradation of the polymers only due to the flow turbulence. It is known
that the extensional viscosity and the relaxation time of the polymer solution are affected when the polymers undergo degradation. Therefore, these properties were measured in this work for fluids with different residence times in the pipe. The work shows that, in fact, the flow turbulence induces an abrupt reduction in the relaxation time of the solution and that this reduction can be directly related to the performance of the friction reducers. Due to the low concentrations of the solutions analyzed and consequent extensional viscosity, difficulties were encountered in characterizing the degradation of the mixture for high residence times in the tube. Nevertheless, the methodology used seems to be promising for more detailed studies on the degradation of high concentration diluted polymers.
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