Steady Asymmetric Flow Of A Viscous Fluid Past A Cylinder

The steady flow of a viscous incompressible fluid past a cylinder is considered. In particular, asymmetric flows, which involve a lift force in addition to the drag, are investigated. The Navier-Stokes equations and the equation of continuity are formulated in terms of the stream function and vorticity. The work may be divided into two parts, an asymptotic solution of the governing equations of motion at far distances from the cylinder, and a numerical solution of these equations near the cylinder. An asymptotic solution to the vorticity is obtained in the form of a Hermite polynomial expansion. This solution is in perfect agreement with Imai (1953). The asymptotic solution involves unknown constants (namely the lift and drag coefficients) which must be obtained from a numerical solution valid near the cylinder. Leading terms of this solution are then used as the boundary condition at far distances in the numerical calculations.;Numerical results are given for the flows past a rotating circular cylinder and an inclined elliptic cylinder for Reynolds number 5 and 20. The influence of the asymptotic solution and grid size upon the numerical solutions is investigated. In the case of the rotating circular cylinder, results are given that are in agreement with unsteady results that are taken to a limit in large time (Badr et al., (1988)). The flow past an elliptic cylinder with ratio of minor to major axes of 0.2 is investigated for various angles of incidence. Results of the symmetric problem are compared to Dennis and Chang (1969). The dependence of the lift, drag and moment upon the Reynolds number and angle of incidence is studied. For both types of cylinder, surface pressure and vorticity distributions given. In addition, plots of streamlines and lines of equivorticity for the flow past the cylinders are presented.

Name thesis:degree_name

Ph D

Year dc:date.issued

1989

Author dc:creator

• Young, Peter Joseph

• Mathematics

Handle dc:identifier.uri

https://hdl.handle.net/20.500.14721/21429

OAI identifier oai:identifier

oai:uwo.scholaris.ca:20.500.14721/21429