Project Details

The addition of small amounts of long-chain polymer molecules to internal turbulent single-phase flows can result in significant drag reduction. In gas-liquid two-phase flows, the expected magnitude of the drag reductions is smaller. However, even smaller levels of drag reduction are potentially relevant for operating two-phase flow pipelines.

In this research, the effect of drag-reducing polymers on single-phase and two-phase flows will be addressed experimentally through observation of variations in flow patterns, measurements of statistical characteristics of the gas-liquid flows and observation of turbulent structures near the wall. To this end, standard and advanced techniques will be employed in flows in circular pipes or square ducts.

The thesis work will consist, in principle, of the following steps:

– Bibliographic update

– Adaptation of the experimental test bench

– Implementation of standard and advanced measurement techniques

– Measurement of relevant characteristics of the flows with and without polymers

– Processing of raw data and physical analysis of the results

– Preparation of thesis manuscript

Prerequisits

Students graduated in Mechanical Engineering or Physics, interested in at least one of the following fields of knowledge: fluid mechanics, optics, image processing, programming, and with good academic performance.

Scolarship

CAPES/Cnpq scolarship and possibility of supplementary grant.

Contact

Luis Fernando A. Azevedo – Lfaa@puc-rio.br  (21) 3527-1181

Fabio J. W. A. Martins – fabiomartins@puc-rio.br  (21) 3527-1168

Project Details

In subsea transport lines, oil initially flows under forced convection, maintaining high temperatures due to the continuous injection of hot fluid. During production shutdowns, forced convection is reduced until it ceases, while the oil inside the pipeline continues to lose heat to the cold marine environment, gradually cooling until thermal equilibrium is reached.

When the fluid temperature drops below the Wax Appearance Temperature (WAT), paraffin crystals precipitate, causing significant changes in the rheological behavior of paraffinic oils. Under these conditions, there is a sharp increase in viscosity sensitivity to temperature, as well as greater dependence on shear history and local shear rates. Under these conditions, the formation of a three-dimensional network of crystals can lead to partial or total gelation of the fluid.

This project aims to evaluate, through numerical simulations, the combined influence of forced and natural convection mechanisms on the evolution of the rheological behavior of paraffinic mixtures during the production shutdown process.

Requirements

Students in Mechanical Engineering, Chemical Engineering, or Physics, interested in the following fields of study: fluid mechanics, computational fluid dynamics.

Scholarship

Opportunity for a Research Initiation Scholarship.

Contact

Angela Ourivio Nieckele  – nieckele@puc-rio.br (21) 3527-1182

Ivan Fernney Ibanez Aguilar – iibanez@puc-rio.br (21) 97572-7447

Detalhes do Projeto

Deposição de parafina em dutos é um problema relevante que ocorre na indústria do petróleo, especialmente na produção offshore em águas profundas. O petróleo produzido dos reservatórios é transportado a temperaturas relativamente altas através das linhas de produção. Devido à troca de calor com o ambiente marinho frio, uma temperatura crítica pode ser alcançada desencadeando a precipitação dos componentes de parafina mais pesados. A deposição da parafina nas paredes dos dutos leva a perdas significativas de produção e custos elevados de remediação das obstruções. O objetivo do presente estudo é reproduzir o fenômeno experimentalmente e ou numericamente em condições estritamente controladas e analisar os resultados, considerando os mecanismos dominantes deste fenômeno, e.g.: difusão molecular e transferência de calor.

Requisitos

Estudantes formados em Engenharia Mecânica, Engenharia Química ou Física, interessados nos seguintes campos do conhecimento: mecânica dos fluidos, transferência de calor e massa, termodinâmica, dinâmica de fluidos computacional, programação e com bom desempenho acadêmico.

Bolsa de Estudo

Possibilidade de bolsas de estudo ou complementação de bolsa de órgãos de fomento.

Contato

Luis Fernando A. Azevedo – Lfaa@puc-rio.br  (21) 3527-1181

Angela Ourivio Nieckele  – nieckele@puc-rio.br (21) 3527-1182

Ivan Fernney Ibanez Aguilar – iibanez@puc-rio.br (21) 97572-7447