Published April 1981 | Version v1
Miscellaneous Open

Boundary layer for non-newtonian fluids on curved surfaces

Description

By using the basic equation of fluid motion (conservation of mass and momentum) the boundary layer parameters for a Non-Newtonian, incompressible and laminar fluid flow, has been evaluated. As a test, the flat plate boundary layer is first analized and afterwards, a case with pressure gradient, allowing separation, is studied. In the case of curved surfaces, the problem is first developed in general and afterwards particularized to a circular cylinder. Finally suction and slip in the flow interface are examined. The power law model is used to represent the stress strain relationship in Non-Newtonian flow. By varying the fluid exponent one can then, have an idea of how the Non-Newtonian behavior of the flow influences the parameters of the boundary layer. Two equations, in an appropriate coordinate system have been obtained after an order of magnitude analysis of the terms in the equations of motion is performed. (Author)

Availability note (English)

MF available from INIS under the Report Number.

Abstract (Portuguese)

As grandezas do escoamento laminar incompressivel, nao-newtoniano, dentro da camada limite sao obtidas atraves da utilizacao de duas equacoes fundamentais: conservacao da massa e conservacao do movimento. Analiza-se o problema da placa plana e o de uma fonte de escoamento plana. Para o caso de superficies curvas da-se um tratamento geral e particulariza-se o problema para o do cilindro circular reto. Para o ultimo caso sao impostas as condicoes de succao e deslize na interface do escoamento. E utilizado como fluido nao-newtoniano, aquele que pode ser descrito pelo modelo da lei de potencia; e foram determinadas grandezas importantes da camada limite para diversos indices de comportamento do escoamento, podendo ter-se uma ideia aproximada de como o escoamento e influenciado pela natureza reologica do fluido. Com as simplificacoes proprias da camada limite e substituindo-se a equacao do modelo, obteve-se um sistema de duas equacoes diferenciais parciais, vinculadas a um sistema de coordenadas, adequado para cada problema em estudo. (Autor)

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Additional details

Additional titles

Original title (Portuguese)
Camada limite para fluidos nao-newtonianos sobre superficies curvas

Publishing Information

Imprint Pagination
89 p.
Report number
INIS-mf--7386

INIS

Country of Publication
Brazil
Country of Input or Organization
Brazil
INIS RN
13703237
Subject category
S42: ENGINEERING;
Resource subtype / Literary indicator
Thesis
Descriptors DEI
BOUNDARY LAYERS; FINITE DIFFERENCE METHOD; FLOW MODELS; INCOMPRESSIBLE FLOW; LAMINAR FLOW
Descriptors DEC
FLUID FLOW; ITERATIVE METHODS; LAYERS; MATHEMATICAL MODELS; NUMERICAL SOLUTION